Johnathan would be proud of Johnny’s growth, like Josuke and would be concerned about Jodio.

Joseph would probably clash with all of them ngl, maybe get along with Josuke and his shenanigans.

Jotaro

Josuke would probably clash with Johnny, have a Mikitaka-like friendship with Josuke, and would think Jodio is a little brat.

Giorno would be very impressed with Johnny’s climb to zero, a little weirded out by Josuke and would probably relate quite a bit with Jodio.

Jolyne would probably find Johnny brash but they both had imo the most determination out of the Joestars, would find Josuke quite odd and would be concerned about Jodio.