E.g. In GTA online
Unfortunately, Sony has strongly opposed cross-play and currently only adds it to certain games. So you can't say that in general.
For GTA online?
Generally you can say no. The games where it works, you can count on my impression of one hand.
This is only possible in the fewest games. It's not possible in GTA.
Yes and there are such stupid things as Rocket League.
PC can play with all games. PS4, XBox, Switch…
But PS4 can only work with PC. Absolutely nonsense.
Yes, others are more open, but the others barely offer Crossplay. There's not much more on the other platforms either.
