I would definitely expect both Logan and Max to be male. However, if someone told me Logan was female, I'd say, "Oh." If someone told me Max was female, I'd say, "What?!"
Isn't Max usually a nickname for both masculine and feminine names? Like a person called Max could be Maxwell or Maxine. Like right now one of the new protagonists in Stranger Things 2 is a girl named Max.
It could be, certainly. Partly I was evaluating this as a question about full names only. And more importantly, Maxine has only recently re-entered the top 1000 at all and is ranked at #874. Max- names for boys are vastly more popular.
That's true––I'm not a fan of Maxine either. I do know some girls named Max, but I don't think I ever heard them use a full-name version like Maxine though. So maybe it was just Max.