Googled around and found this page: https://forum.proxmox.com/thre…to-5-3.52622/#post-243591
which implies I just needed to purge stuff. I've done that and I'm past the behavior above. I got one of my two boxes back up. The other one I'm having trouble seeing the ZFS plugin, but I assume once I get that back somehow (I'll upload the plugin manually if it comes to that) I should be good.
I did this like they write:
apt -f installapt purge insserv sysv-rc initscripts
openrcapt update && apt full-upgrade
After that i tried installing ZFS again but it didnt worked.
I rebooted my NAS and reinstalled zfsutils-linux manually
apt install zfsutils-linux
After that openmediavault-zfs automaticly show up again and i was able to impoort my pools
Thanks for your support guys