BAMF team for womenverse
Faith Lehane (Buffyverse), Katherine Pierce (Vampire Diaries), Cara Mason (LotS), Sharon "Athena" Agathon (BSG), Regina Mills/Evil Queen (OUAT)
A team that you would definitely not want to fuck with! All bamf's in their own right, and all tip toe on the line between good and evil.
Faith and Cara - would be the muscle of the group. Faith has her slayer abilities and Cara has her Mord'Sith ones and extensive training in all things torture and pain. I can see them both getting along really well, yet fighting a lot; both trying to learn something from the other, torture techniques and the like. They would keep each other in line. Also Cara would be the only person in the group to keep Regina in line whenever she got outta control. Faith would be the one to keep Katherine in line.
Athena - would be the computer or technology person in the group, for hopefully obvious reasons. I can also see her as the "glue" to the group, the one to keep everyone from killing each other and being the voice of reason in the fights and strategy sessions. She also has a lot of military intelligence that could come in handy when planning missions and such, so she would take one of the leadership roles in the group.
Katherine - would kinda be the grifter of the group. She is the seductress and actress, with many sides. Plus she has that cool vampire power of compulsion that would really come in handy in a lot of situations.
Regina - would probably take on the other leadership role opposite Athena. I think she has a lot of experience that would come in handy in a lot of situations, but would still rely on the knowledge and experience of the other members of her team. Plus her magic would definitely come in handy.