Linux has nothing to do with mods, Unity does. Unless somebody wrote a hook and compiled it for Windows (like aimbotters do), any normal mod, which as far as I know are mostly XML, will work on any OS because the game loads and parses the mods, not the OS. If you have something that goes outside the bounds of the game to mod stuff I would be wary because an EAC or VAC ban is no fun.
As for the rest, why do you need ESXi? I have run four Ark servers, which are FAR more resource-demanding than 7 Days, on a single box. The box is a SuperMicro setup, 64GB of ECC DDR4, RAID10 BTRFS SSD, and two octa-core Xeons. There is no need to use virtualization here and it will lower your performance. It sounds to me like you've read a lot of info and may be a tad burned out on the avalanche of information. The point is, no matter what OS you choose to use, you do not need virtualization in your scenario. You can run a hundred 7 Days server on Linux or Server 2019 on bare metal if you have the resources.
My advice for your unique setup, would be to choose a powerful OS (not a workstation OS like 10) and put it right onto your server, write four configuration files, and run all four right there.
Beelzybub, I thought you were a team member who could answer that query. I see now you are not. You've just been here forever.