im no programmer but I think you’d have to have some kind of master matchmaking server to do this. Have a button for the clients that says “I wanna play”. That communicates to the server, telling the server the players IP and relevant game info. Then clients retrieve that information, and get a list of all games (you can make it hide the IP, of course). Then in the background tries to connect them.
I don’t see why you couldn’t do this fairly easily with blueprints, the only hard part is having a server and creating the communications system. I don’t actually know anything about how to get the server client to a server, or how dedicated servers really work at all. But maybe this info can help you get started?
Heck maybe I’ll work on making a nice “lobby/matchmaking” template just for kicks. I wouldn’t mind learning how to do this. The only thing I don’t know and worry about, is how much would a matchmaking server like this cost?