https://techcrunch.com/2019/10/10/steam-will-soon-let-you-play-local-only-multiplayer-games-with-far-off-friends/
 
Co-op video games are wonderful. Alas, it’s not always possible to get everyone in front of the same TV — and not all co-op games have online play, so playing across the internet is out. With that in mind, Valve has been working on something it calls “Remote Play Together” that it’s planning on rolling into its Steam  game launcher later this month. By more or less tricking the game into thinking all players are in the same room, it’ll let you remotely play with your friends generally local-only multiplayer games. Valve published on its developers-only Steamworks site a note about the upcoming feature, first noticed by PCGamer. The note quickly made its way to the Unity developer forums.
“Your local multiplayer games will soon be improved with automatic support for Remote Play Together on Steam,” it reads. “All local multiplayer, local co-op, and split-screen games will be automatically included in the Remote Play Together beta, which we plan to launch the week of October 21.”
 
I think this is a very nice addition from Valve. 

That's pretty cool.  

Pretty cool, I'd love to try it

Eh i'm skeptical Steam streaming has gotten a lot better over time but i hands down would still rather use Parsec. I dunno if Valve will allow online multiplayer to old rom games like Parsec does. Playing Mario party on pc online tricking it into thinking its local coop simply the best!