To be available in an opt-in Beta on Steam, SCS Software are officially bringing online multiplayer to both of their truck sims with Euro Truck Simulator 2 and American Truck Simulator.
Read the full article here: https://www.gamingonlinux.com/2021/05/scs-put-up-an-open-beta-for-multiplayer-in-euro-truck-sim-2-and-american-truck-sim