It would be much easier and more efficient if translators could attach their language files directly to the existing mod file via the "Files" tab on the original mod page (upload icon for translations, right next to each file). This way, all available translations would be visible and easily accessible to users.
These attached translations would initially be marked as "not approved." The original mod author would then have the option to review and approve them if desired.
Additionally, translators should be able to add a note when uploading their translation.
Users should also have the option to endorse the translator directly on the note page, note box or a popop to show appreciation and support for their work.