• Mac
• Windows
• QEMU
• VM

This very helpful post by GitHub user niw explains how to use QEMU to run a Windows virtual machine on an M1 Mac.
Currently, I've only got a VirtualBox VM on an old 2012 Mac mini (Intel Core i5-3210M), which is just painfully slow. With help from the post linked above, I can now run a much more usable VM on my M1 MacBook Air.

The post is very detailed and helpful, but I thought I'd add a couple of things I stumbled over:

• The version of QEMU available on Homebrew (6.0.0 at the time of writing) does not work on macOS 11.1 and above due to a bug.
• Downloading and compiling QEMU 6.1.0 is not an option either, patches are needed to support Apple's Hypervisor framework.
• For some reason, the QEMU command-line-interface does not work with relative paths. That was a major headache before I noticed.