I know GS3 uses Unreal Engine and is an Epic Games Store exclusive. I don’t know how far the deal with Epic has gone but I’m super curious about whether crossplay will come. I tend to play games on my PS4 Pro as my PC isn’t very powerful. I know GS3 isn’t available for PS4s but perhaps if it will, I’d love to know if it’d let me play with my PC friends. Just makes it hard to recommend to my friends.
All we really know currently is that they are considering Crossplay but no guarantees. Same with ports to old gen consoles.