Honestly, we will probably be getting three guests again. Remember back in MKX when they were teasing KP2? Everyone thought we would be getting the fightable story NPCs -- Sindel, Rain, and Baraka -- then one more character like Noob Saibot or Jade.
But nope, we got Bo' Rai Cho, Triborg, Leatherface, and Alien instead. Another two guests, an MK character that no one was expecting, and then the cyborgs which were fairly requested but weren't story mode NPC status.
Based off of the leak, we know that Fujin, Sheeva, and The Joker are most likely coming. Then of course Kombat Pack 1 has three MK and three guests, which is a format they will probably stick with. So if I had to feel in the blanks, I think it would look something like this:
- Fujin
- Sheeva
- Takeda
- The Joker
- Doomslayer
- Pennywise
Fujin for a 3D-era fighter, Sheeva for a Trilogy-era fighter, and Takeda as a New-era fighter (or whatever you would call it).
Then a comic guest, a video game guest, and a movie guest.
Maybe not Pennywise because they wouldn't want two clown characters, but they usually do a horror character character of some kind and they are kinda running out of material especially if they are adding Ash Williams. Freddy Krueger, Jason Voorhees, Leatherface, Alien, and Predator have already been done. I see no reason from them to not do Pennywise after the new movies, plus I think Ed on Twitter said maybe they will do Pennywise another time or something like that.
Aside from that, I think we could get a Sweet Tooth skin for The Joker for PlayStation players and then a Thunder skin for Nightwolf for Xbox/PC owners. Simply because Ed has mentioned both these characters on Twitter, specifically asking if we wanted a Thunder skin and beforehand asked how they would make Sweet Tooth work in the game (because console exclusive characters are off the table. A skin would work, though).
This is assuming that Kombat Pack 2 will be a full pack just like the first one, and that Fujin, Sheeva, and The Joker aren't just bonus releases/apart of a mini-off season pack.