So I've got cyberpunk phantom liberty 2.0 but to update to 2.1 heroic game launcher wants me to download the hole game again, gog galaxy through wine is not an option so I'm looking at xdelta3 and innoextract to manually patch game files. But I'm hitting a break wall and seems to fail with every attempt using xdelta3
Heroic is working on this feature and you can try it out if you want to currently it just isn't deemed stable. Here is the PR: https://github.com/Heroic-Games-Launcher/HeroicGamesLauncher/pull/3020