I have been sitting on this ask for a while because Oh Boy, was this a thinker. I had to make a graph and chart in order to answer this question.

I can see Max getting along with Dave and Sollux.

Suzy would have a crazy girl squad of Jade, Vriska, Nepeta, and Terezi.

Isaac can be with Rose and Kanaya.

Starchman would just have a powwow of a bunch of them like John, Jade, Terezi, Tavros, Nepeta, and Kanaya.

PJ would be friends with Tavros and Nepeta.

Ed and Isabel, would be friends with Terezi, Jade, and Karkat.

Dimitri can be cool with Rose and Gamzee.

Garcia is also chill with Gamzee and Sollux.

And Johnny, my wildcard child. I get the feeling that he would like everyone, in his mind anyway. But he would definitely fight with Equius and Karkat. So the real question is who wouldn’t like him.

My money is that Karkat and Eridan would hate him for his strange ass behavior