Maybe it's just me, but in female-only community, I'm using female as part of a composed adjective. I'd say male-only community too, it just feels more natural. In fact, in an earlier comment I wrote women only, and then writing man only felt SO bad that I changed both to female and male.

Now that I think about it it's probably because I used man instead of men. I'll change both back but OOP miiight have followed my logic? Idk