Ken will be in Smash Ultimate, likely as an Echo Fighter as Ryu.
Incineroar will be in Smash Ultimate as a Playable Character.
Minecraft will be represented in some form for Smash Ultimate, either as a Character, a Stage, an Assist Trophy, or whatever collectibles this game will have (Trophies, stickers, etc...)
This game is going to have another Square Enix rep, that will either be as extremely early DLC or in the base roster. He didn't confirm or deny if it would be Geno, Sora, etc. due to the fact he feels this could put the jobs of his sources at risk due to the way Square Enix is handling things, as they are telling many different employees who the character is so they can single out the moles. He also feels this character is a character that would be best for everyone if they were revealed naturally.
What I'm about to say is less of a leak from him, and just something interesting to note of what he said:
He is saying that Geno is one of the characters Square Enix would pay less attention to if leaked, due to the fact others are already leaking him so often. Whether that confirms or deconfirms the Square Enix character he is leaking is in fact Geno, I'll leave up to you. I've mixed feelings on this one.