Just an idea:
- Get an HDD
- Use
ddto clone your NVME Windows drive. - Install Linux on your NVME.
- Boot Windows from the HDD as you find you need it (which I suspect would be a lot less than you think).
- If you find you need to go back to Windows, just reclone onto the original drive.
I bet you'll eventually reclaim the HDD, though. I kept mine for about two years, and I nuked it last week, because I hadn't even opened it, much less booted it, in over a year.