Okay, I'll be that guy this time: Why the downvotes? This is a bit hacky and only allows temporary systems, but it appears to be functional, free-as-beer, and works fine for these random one-off cases.

Per the license terms [1]:

You may use the software for testing purposes only. You may not use the software for commercial purposes. You may not use the software in a live operating environment.

[1] - https://az792536.vo.msecnd.net/vms/release_notes_license_ter...

Apart from this being essentially an EULA an therefore not necessarily binding in your country, I don't think that doing the stuff described in the OP would violate these terms.

And if it does violate the terms, let's remember we live in the real world and absolutely nothing will happen to them as a result

Don't worry about the downvotes friend, they are merely silly internet points. Someone might come across the comment in the future and find it helpful, and that's all that matters.

Well said. As the person you replied to, I find your answer helpful. Thank you!

Used this to run some Windows-only NES Classic / SNES Classic "hacking" program thingy (hakchi2? Something like that) to add more games to those two devices. Worked great. Wine was a no-go because the program itself did some stuff with (Windows) drivers when needed. VirtualBox. Worked great. I have a Win10 license and could have dug it out but this was easier.

Amusingly enough, all of the low-level hardware access stuff in hakchi2 seems to be done through Windows ports of various Linux-based libraries and tools. The Windows drivers are just there to emulate the normal Linux APIs for low-level USB access. In principle, it would be possible to just chop out all the layers of emulation and drop in the original Linux USB access library using the actual Linux APIs (compiled as a Wine-style DLL so the Windows code could use it) and everything should work fine.