Crossplay problems on ps4 and pc

I have a problem to play crossplay with a friend, i play on ps4 and he on pc, we also are involved on the epic store account to crossplay, but nothing happens, Incant invite him. (Sorry for bad english)

You can’t crossplay invite sadly

I have a huge crossplay problem… It makes crossplay not even possible… The issue is that my frame rate goes down as low as 15 fps. How am I supposed to compete with people who scoff at a measly 60 fps?