not sure exactly what metadata you mean, i don’t really know well about NTFS’s advanced features. i just tend to have some version of windows installed in another partition or a drive and ocasionally copy files from and to it, never had any issues. ntfs-3g is a bit slow tho due to being FUSE.

the winehq compatibility db is outdated in some cases, so it’s best to just try for yourself and see if it runs ok. if it doesn’t work well, it would usually be very obvious. (crashes, glitches, etc)

yes LTSC 2021 and 21H2 is the same thing

massgrave generates a legit activation ticket unlike the old windows hacktivation methods like KMS (KMS haktivators used to run a local activation server baiscally). so it even auto activates after reinstalling just like a legit key. no downsides other than the fact it’s not “legal”, but that’s the same for those sketchy keys since they are also usually violations of Micro$oft EULA.