Here is the current status of porting omv-extras plugins to OMV 6.x. If the plugin isn't on the list, it won't be ported or is a core OMV plugin.
25 of 25 - done
openmediavault-anacron - done
openmediavault-apttool - done
openmediavault-autoshutdown - done (thanks to nrandon)
openmediavault-backup - done
openmediavault-borgbackup - done
openmediavault-developer - done
openmediavault-downloader - done
openmediavault-fail2ban - done
openmediavault-flashmemory - done
openmediavault-kvm - done
openmediavault-locate - done
openmediavault-luksencryption - done
openmediavault-mergerfs - done
openmediavault-minidlna - done
openmediavault-omvextrasorg - done
openmediavault-openvpn - not going to port
openmediavault-remotemount - done
openmediavault-resetperms - done
openmediavault-rsnapshot - done
openmediavault-sftp - done
openmediavault-snapraid - done
openmediavault-symlinks - done
openmediavault-tgt - done
openmediavault-wakealarm - done
openmediavault-wireguard - done
openmediavault-wol - done
openmediavault-zfs - done
openmediavault-compose - new!
openmediavault-cputemp - new!
openmediavault-diskclone - new!
openmediavault-webdav - in progress
openmediavault-mergerfsfolders - should be automatically migrated to openmediavault-mergerfs when upgrading from 5.x to 6.x
openmediavault-unionfilesystems - should be automatically migrated to openmediavault-mergerfs when upgrading from 5.x to 6.x