Enable Custom Language for Specific User

Now that you have added one or more custom languages, you can specify which language a particular user will see in their view of the Control Panel. For this:

  1. Make sure that the required locales are added in Settings > Configuration > Interface  Locales field. Unless you add the locales in Settings, customers will not be able to switch locale.
  2. Go to your Control Panel's Users and Groups menu.
  3. Click a user's name.
  4. On the page that appears, click the Edit Profile tab.
  5. Choose your custom language from the Locales drop-down list.
  6. Click Save.