Stuff needed for windows guest
ISO with drivers and guest agent from here:
https://docs.fedoraproject.org/en-US/quick-docs/creating-windows-virtual-machines-using-virtio-drivers/index.html#virtio-win-direct-downloads
Stable release is currently 0.1.171
Need to install most of the drivers, and also make sure the virtio device model is specified for the devices in the VM configuration.
Windows SPICE agent AKA vd_agent (for copy-paste) - currently at 0.9.0
https://www.spice-space.org/download.html
Support for newer OpenGL versions - instead of only OpenGL1.1
Original info here
Download from here and run systemwidedeploy.cmd and choose option “1. Core desktop OpenGL drivers”
https://github.com/pal1000/mesa-dist-win/releases
It will not be fast - but it will enable some OpenGL apps to run at least.