Can I participate in Fortnite tournaments as a PC player with a Ps4 player?

I hope the question is understandable. I wanted to ask, because there are also separate lobbies for PC and Ps4 players. There are also tournaments and then I don't know if that would even be allowed.

In public everyone is in the same lobbies, no matter if pc switch console or mobile
PC is one half of the tournament and consoles and mobile the second

So you can only play with pc players

Yes, is allowed.

Otherwise you play together.