I just created a new “French” learn category to try this out: À propos de la catégorie "Apprendre en Français"
If that works well I propose to roll out other languages by order of popularity. Or if somebody is very motivated I can create a section for their preferred language.
EDIT: I will need an intro written in the target language for the group description. It should include that the goal of the category is for people to ask questions in their native language if they are not fluent in English.