Jip, Forza Horizon 3 was full cross play between PC and Xbox, and you don't even notice who is on which platform when playing. but beware, Forza is a beast on PCs. Have not been the most friendliest or most stable versions of the game. Lots of reported crashes and glaring performance issues on some cards. Mostly the game has favoured an Nvidia setup over AMD. Newer cards perform better though.
But what I like most about the fact that there is cross platform support is the fact that you'll get friends from different platforms' drivatar to drive against. Nothing like driving single player, and suddenly seeing a name of a friend pop up and you have to drive against their drivatar. I really think that's Forza's biggest advantage.




I see this is an Xbox Play Anywhere title, so maybe I'll pick it up for PC. Apparently there will be cross platform multiplayer, so that could be fun!
