Far Cry 3 and SteamVR looked to be broken installs i probs copied over from an old device. they weren't even showing up as installed in the steam library, i deleted the folders.

As for 7 days to die, i deleted the EasyAntiCheat_Setup.exe and ran verify integrity of install files. it didn't get redownloaded so i dunno 🤷‍♂️

The "Last Played" time for it was July 14th 2014, so it's unlikely it has ever run on this machine

There is a change for a cross OS malware but it's probably still quite small.

I would just remove them, and then if they dont re-appear after checking game file consistency then its's mostly likely not a false positive.

But if you know that last playerd is most likely before you installed current OS then it should be clean. I would check user level autostart and cronjob (so mostly stuff in $HOME/.config) places if something didnt get added, go ahead with life.

Unless you are doing banking and other critical stuff on this machine then I would be thinking of hardedning the OS in some way and/or reinstalling.

Consider pulling those through https://www.virustotal.com/