While the vast majority of Growth features will be translated via TranslateWiki, one outstanding element are page aliases, which are the strings that go in URLs for things like "Special:Homepage", etc. It would be nice, but not critical, if we had a solution to easily translate those.
|Open||Goal||Trizek-WMF||T228980 [goal] Deploy Growth features on wikis requesting them|
|Open||Trizek-WMF||T247507 Scale: deploy Growth features to 100 wikis|
|Open||None||T250243 Scale: translation of aliases|
Change the alias files in the repo (for extensions). In core it's at https://github.com/wikimedia/mediawiki/blob/master/languages/messages/MessagesEn.php
You can't do it on translatewiki for a long time due to T109235: Re-enable Special:AdvancedTranslate on translatewiki.net