I would suggest to backup the clusternode and restore it on the new hardware... I did a test and it worked for me, please have a look: PVE-Server disaster recovery from PBS-Backup
Sorry for the delay... the replacement took 2 months to arrive.
The cloning of the disk failed (or I made some error).
I took the coward's way and added the new hardware as a separate machine to the cluster, moved the vms and decommissioned the old hardware. It was the easiest way...