Ah yes. I too use qvm-block for my sata devices.
What I neglected to mention was that several of my USB devices implement hardware encryption (that replaces a small read-only volume with the main read-write volume after unlock).
The strategy choice then was a) unlock via sys-usb and utilize qvm-block or b) connect usb chipset to disposable VM and unlock there. I chose the latter.
B
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