back in the day i used to play cracked left 4 dead online using garena (it was basically a game server software where users could join rooms and they would have servers. i mostly remember there being south americans/slavic people on there. was quite interesting. afaik it would use steam group servers to connect (which may could be a lan type thing but idk).

idk how it works now but i’d imagine it would be tougher now with current games acting more like a live service. if you get bored of playing with slavs every time then it’s time to buy the game.