If you want to use virtual disk as bootable USB device or use ISO file as bootable USB device look at this thread

https://communities.vmware.com/t5/VMware-Workstation-Pro/Idea-Feature-Suggestion-Useful-to-have-vmdk...

The thread offers both optoons (using virtual disk as USB device or ISO file as USB device). Whether it is bootable or not would depend on the contents of the virtual disk/ISO.

To boot from the virtual USB device, the same rules/methods in my earlier reply (i.e. VM needs to be using UEFI, use Power On to Firmware). The exception is that you don't need steps (2) to (4) as specifying the virtual USB in the vmx would already make it connected and you should already see "EFI USB" as a boot option the first time you powered on to firmware