I think so. I haven’t done this before, but I believe that sys-usb is a regular VM with a USB controller attached to it. (@ludovic Is that true?) If I’m correct, you could clone your existing sys-net and assign a USB controller to it.
One way to do that is using the Qube Manager, or via the command line, like described by the 6-step instructions in this forum post.
I let you figure out how your own USB controller is called, and replace sys-net by the name of your own clone. As far as I can tell, USB controllers have names like sys-usb:3.3.
Again, I’m not on my machine, and I’m not able to actually try this, please be careful and use your judgment, or wait for someone else to confirm! 