There's no supported way to use create a datastore from usb.
USB arbitrator will claim the USB for passthrough and won't format it with vmfs.
But you can create VMFS volume in FC,iSCSI or even local iSCSI disk.
Anyways you can copy the VM files using Veeam.
The Veeam Backup and Replication allows you copying files from ESX(i) datastore to whatever location you want.Try it out!!
Hope this helps!!!
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Regards,
SatyS
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