Thats tough, technically yes they could, but it wouldn't be ideal. I mean I guess u could try it and they might be ok, but I don't know how happy they'd be.
Like it is for a variety of other things, it depends on the betta itself. I personally tried 2 female guppies with both of my bettas. Darts simply chased them away but Mystic was out to kill So now they're seperated.
Thanks, I decided I wouldn't try it as I don't want to risk it and I'm not sure my filter could handle the waste so I just put them in my big tank, thanks for the replys I might try it later. probably not