Hi, you can set them in the configuration of the VM, but currently that is not possible over the webinterface.
First get the current configuration and search for the line with your disk:
qm config VMID
This could look like (for example):
scsi0: sandisk-store:vm-101-disk-1,discard=on,size=200G
Use that as base and add the serial number, wwn, .. attributes. For all available see
https://pve.proxmox.com/pve-docs/qm.1.html (search for "--ide" or "--scsi")
For example, with the existing line from above you could do:
qm set VMID --scsi0 'sandisk-store:vm-101-disk-1,discard=on,size=200G,serial=1234-33-31,wwn=1234'
as you see this works not only for ide but also for scsi, which should be preferred if possible.