Considering their popularity and use at Worlds, my guesses will be: Maokai/Irelia Lee Sin(SKT T1 K) / Kha'Zix Zed (SKT T1 K) / Orianna (TPA) / Yasuo / Talon Thresh or Janna Tristana / Kog'Maw / Corki (Fnatic)
I think that the ones who already have a team skin won't have one though.
They need to put a skin on Wight till next season champions
Given that they've always used the champs that were played by the winning team in the last game, there's a very high chance that it'll be Rengar, Corki, Janna, Kassadin, Orianna. Though we've not yet seen what they do if there's a duplicate champion from a previous season, so we'll see on that. But that probably guarantees skins for at least Rengar and Kassadin, though.
I know some people would complain if they go on to make the duplicate skins for Janna/Corki/Ori, but I actually think they should. The skins commemorate a real-life event. You can't change what actually happened.
Top-Singed Jungle-Rengar (duh) Mid-Talon Bot-Twitch Bot-Thresh or Janna
I'm thinking Jayce and Janna will be in there for sure. Probably not Maokai - i'm thinking Ryze.
