Assassin's Creed - Lutris

Play all your games on Linux. Lutris is an Open Source gaming platform for Linux. It installs and launches games so you can start playing without the hassle of setting up your game. Get your games from GOG, Steam, Battle.net, Origin, Uplay and many other sources running on any Linux powered gaming machine.

Assassin's Creed III - Lutris

Assassin's Creed Unity - Lutris

Assassin's Creed Valhalla on Steam Deck - optimized settings

It appears that Lutris is no longer viable - Support - Lutris Forums

Lutris 0.5.11 Released - Official Discovery Store Support - Steam Deck HQ

Ubisoft Connect - Lutris

Assassin's Creed Origins - Lutris

Assassin's Creed Odyssey - Lutris

Ultimate guide to install any game on Steam Deck with screens - Lutris, Bottles, just Steam. : r/LinuxCrackSupport