Is this a male or female?

Female bettas can be just as aggresive as males and when sororities are first setup, the establish the pecking order, and a very aggresive during this time IME. So it could easily be a dominant female and they are establishing the pecking order within the tank

Yes. I agrees with the above posts, at the time I made my first post the picture wasn't working but from the picture it looks like a male as it has longerc ventrals, no visible egg spot, and a tiny beard