User profile fields translated but not showing up on user account modification and registration
After you translated the select list options of your (user) field, make sure that you ALSO change the Format of that selection list from Default to Default Tanslated, which you can do via "Manage Display" (located at /admin/config/people/accounts/display). Similar to what is explained in this comment also ...

Note: same is true for using such fields within a content type.