This is very specific, but I remember the first “easter egg” I ever noticed in a game.
In the PS3 game “Ratchet & Clank: Tools of Destruction”, at the start of the first level a statue of a character named Captain Quark gets blown up around the head & shoulders. The bottom half of the statue remains in the level.
In the standalone expansion / sequel, “Ratchet and Clank: Quest for Booty”, there’s an area of water you can swim in on the main hub island. Under the water you can find the upper half of that Quark statue buried partially in the sand.
I’ve always thought it was a subtle joke that the force of the explosion propelled the statue to another planet. It could just be a simple Easter egg too.
You can see what I’m talking about in these videos:
At 3:10 in ToD: https://youtu.be/GcQIZq1TPrk?t=190 At 14:20 in QfB: https://youtu.be/M9Hkz2gbGxY?t=852
You could try running the Android version through Waydroid.
Found this after searching for “Steam Deck Waydroid”, it might be helpful IDK: https://github.com/ryanrudolfoba/SteamOS-Waydroid-Installer