Hey, kags!
Okay, you definitely need to disclaim all four anime series as well as Battle Royale. Your bet best is to put: "See full disclaimer in Chapter 1" in the disclaimer field.
Than, in chapter 1, you should have something like this:
"I do not own [Anime 1], [Anime 2], [Anime 3], [Anime 4] and Battle Royale, I make no profit from this story."
I'm going to add one caveat... if you use any of the actual actors from the movie of Battle Royale in your fic, you need a Celebrity disclaimer. If that's the case, let me know and I'll tell you what you need.