diff --git a/changelogs/fragments/2731-mh-cmd-locale.yml b/changelogs/fragments/2731-mh-cmd-locale.yml
new file mode 100644
index 0000000000..607a7b89b7
--- /dev/null
+++ b/changelogs/fragments/2731-mh-cmd-locale.yml
@@ -0,0 +1,3 @@
+bugfixes:
+  - module_helper module utils - ``CmdMixin`` must also use ``LC_ALL`` to enforce locale choice (https://github.com/ansible-collections/community.general/pull/2731).
+  - xfconf - also use ``LC_ALL`` to enforce locale choice (https://github.com/ansible-collections/community.general/issues/2715).
diff --git a/plugins/module_utils/module_helper.py b/plugins/module_utils/module_helper.py
index d241eba5af..d9ab83a52b 100644
--- a/plugins/module_utils/module_helper.py
+++ b/plugins/module_utils/module_helper.py
@@ -487,13 +487,16 @@ class CmdMixin(object):
     def run_command(self, extra_params=None, params=None, *args, **kwargs):
         self.vars.cmd_args = self._calculate_args(extra_params, params)
         options = dict(self.run_command_fixed_options)
-        env_update = dict(options.get('environ_update', {}))
         options['check_rc'] = options.get('check_rc', self.check_rc)
+        options.update(kwargs)
+        env_update = dict(options.get('environ_update', {}))
         if self.force_lang:
-            env_update.update({'LANGUAGE': self.force_lang})
+            env_update.update({
+                'LANGUAGE': self.force_lang,
+                'LC_ALL': self.force_lang,
+            })
             self.update_output(force_lang=self.force_lang)
             options['environ_update'] = env_update
-        options.update(kwargs)
         rc, out, err = self.module.run_command(self.vars.cmd_args, *args, **options)
         self.update_output(rc=rc, stdout=out, stderr=err)
         return self.process_command_output(rc, out, err)
diff --git a/tests/unit/plugins/modules/system/test_xfconf.py b/tests/unit/plugins/modules/system/test_xfconf.py
index 1002952ce3..8eb898b815 100644
--- a/tests/unit/plugins/modules/system/test_xfconf.py
+++ b/tests/unit/plugins/modules/system/test_xfconf.py
@@ -49,7 +49,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/inactive_opacity'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '100\n', '',),
                 ),
@@ -69,7 +69,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/i_dont_exist'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (1, '', 'Property "/general/i_dont_exist" does not exist on channel "xfwm4".\n',),
                 ),
@@ -89,7 +89,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/workspace_names'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, 'Value is an array with 3 items:\n\nMain\nWork\nTmp\n', '',),
                 ),
@@ -109,7 +109,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/use_compositing'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, 'true', '',),
                 ),
@@ -129,7 +129,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/use_compositing'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, 'false', '',),
                 ),
@@ -155,7 +155,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/inactive_opacity'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '100\n', '',),
                 ),
@@ -164,7 +164,7 @@ TEST_CASES = [
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/inactive_opacity',
                      '--create', '--type', 'int', '--set', '90'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '', '',),
                 ),
@@ -190,7 +190,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/inactive_opacity'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '90\n', '',),
                 ),
@@ -199,7 +199,7 @@ TEST_CASES = [
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/inactive_opacity',
                      '--create', '--type', 'int', '--set', '90'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '', '',),
                 ),
@@ -225,7 +225,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/workspace_names'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, 'Value is an array with 3 items:\n\nMain\nWork\nTmp\n', '',),
                 ),
@@ -235,7 +235,7 @@ TEST_CASES = [
                      '--create', '--force-array', '--type', 'string', '--set', 'A', '--type', 'string', '--set', 'B',
                      '--type', 'string', '--set', 'C'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '', '',),
                 ),
@@ -261,7 +261,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/workspace_names'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, 'Value is an array with 3 items:\n\nA\nB\nC\n', '',),
                 ),
@@ -271,7 +271,7 @@ TEST_CASES = [
                      '--create', '--force-array', '--type', 'string', '--set', 'A', '--type', 'string', '--set', 'B',
                      '--type', 'string', '--set', 'C'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '', '',),
                 ),
@@ -295,7 +295,7 @@ TEST_CASES = [
                     # Calling of following command will be asserted
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/workspace_names'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, 'Value is an array with 3 items:\n\nA\nB\nC\n', '',),
                 ),
@@ -304,7 +304,7 @@ TEST_CASES = [
                     ['/testbin/xfconf-query', '--channel', 'xfwm4', '--property', '/general/workspace_names',
                      '--reset'],
                     # Was return code checked?
-                    {'environ_update': {'LANGUAGE': 'C'}, 'check_rc': False},
+                    {'environ_update': {'LANGUAGE': 'C', 'LC_ALL': 'C'}, 'check_rc': False},
                     # Mock of returned code, stdout and stderr
                     (0, '', '',),
                 ),