[nix23]

Keep in mind that your mounted NFS needs to support xattrs too :)

mount -t nfs -o user_xattr

I just found out that ~only? the Solaris/illumOS NFS-server supports that, and the Linux Client since Kernel 5.9

With all that information..i honestly would just make a dump of my FS and backup the dump, terrible i know.

[formerly_proven]

This is the advantage of the "newfangled" backup tools which don't just copy files from A to B and can do (but not always do!) a much better job at a) not caring about your backup destination's file system b) not losing data that's more complicated than "name and contents".