Originally Posted by maotd

It's true. But unfortunately I have not these girls. In the same logic, Southern Cross is bad in a counter team since her skill decrease the skill boss rate aka multiple counter chance. But I have nothing more with a defense buff :/

Very true, we just have to do with what we have available. That said, Southern Cross isn't really a bad choice. She does have a Defense Buff, and she is very useful against bosses who have a single target attack for their special. Given a choice between a "normal" attack against your girls or a single target special attack, I'd gladly take the normal attack. It's just the AOE bosses for which she isn't ideal. Not ideal, but certainly not bad either.