They will not get nerfed, because there are many other teams that can win against them.

If they nerf that sailor sakura lineup, then they might consider nerfing this. I don't see it happening though.

This is a BP based game as well, not just solely on ninjas, and I can say that the lineup mentioned is defeatable. Tenten launches before my main, but I can still make it through.

Just try raising your BP and trying again, although I know this isn't the answer you want. Good luck!