yea but i suggest you do alot of research, wildbetta arent meant to be kept in communties really, id ask Wildbetta for advice though.
I don't see why not? bettas and harlequins are both at home in soft acidic waters so water chemistry won't be a problem and some are quite peaceful (like the imbellis) so aggression wouldn't be a problem either.
Most people keep wild bettas in smaller tanks so a community isn't really an option but if you've got the space, why not? I think its just a case of finding species that live in similar environments to them really.