I have a desktop and a steam deck. I would like to setup some old games I have on disc on the desktop. Then compress them and decompress on my Steam Deck without doing the full install again. I understand that with wine/proton prefixes they should be installed to a “fake c:/ windows hierarchy” can I just compress that and copy to a different Linux machine? Does it save which proton version was used? If I use something like Lutris or bottles can I import into them?
If they are all installed in the same wine prefix you could back up everything in one go by archiving the “.wine” folder in your home. that will include all applications installed in wine and all settings for those applications.
if you want to separate them into one archive per app you should look into wine prefixes, otherwise you would need to identify every folder a given app created during installation and archive those together manually, which can be very tedious.
What about graphics drivers? What if the desktop has an Nvidia GPU and the steam deck is AMD. Would that even matter?
No, you can copy wine prefixes around all you want. You may have to adjust the graphics settings in the games though.