For the target OMV user the device file and the mount point of the file system is somewhat irrelevant. OMV does not use labels anymore because they made more troubles than they help.
What is your target user?
What troubles did labels cause? I've been using OMV since 3 or 4 and never had an issue with labels. I've ran OMV on an rpi4, an Odroid N2, an Odroid H2, and currently a R5 3600 with like 15 disks.......no issues with labels