Gouramis are one of those types of fish that need a manual. Some mix, some don't and as always, YMMV
! As for the female betta, that is a bad idea. Female bettas, like the males, will fight with other fish that resemble them and will nip at nice looking fins. I had two females together in a 50 gal
and they tried to tear each other apart. Now, one lives with my Badis with no problems and the other one cannot live with other fish.