If you have a VM named lets say `example` with this volumes defined:

        volumes:
        - dataVolume:
            name: dv1
          name: datavolumedisk
        - cloudInitNoCloud:
            userData: |-
              #cloud-config
              password: fedora
              chpasswd: { expire: False }
          name: cloudinitdisk

and then you will try to hotplug dv1 DV/PVC it will succeed and add dv1 as an extra volume with name dv1

virtctl addvolume example --volume-name=dv1 --persist

Ending with volume list of:

      volumes:
      - dataVolume:
          name: dv1
        name: datavolumedisk
      - cloudInitNoCloud:
          userData: |-
            #cloud-config
            password: fedora
            chpasswd: { expire: False }
        name: cloudinitdisk
      - name: dv1
        persistentVolumeClaim:
          claimName: dv1
          hotpluggable: true

I would expect the addvolume to reject trying to add the same DV/PVC with 2 different names in the VM volumes list.