Tried booting Venus OS 2.7_4 Large on Rpi 3B and 4 from USB/SSD without success. (Raspberry OS from both USB and SSD boots OK).
USB/SSD would make more sense now that SignalK and Node-Red are included in the Large version.
Cheers
Igor
P.S. Instructions imply USB stick should be bootable but still no go:
"For now not that easy yet: installing and updating is done using the offline install method: with usb stick or sd-card."