I have a USB HDD that I'm hoping to install Windows on for a few games and other pieces of software. I know my load times will be miserable, but how poorly will things run once on ram? Lastly, Windows does like to screw with other operating systems on the same drive, will it play nice with my main drive as long as it's on the HDD?
Update:
I tried this and it works great. Granted, you need a good book for installing games (it took me around 2 hours for both Battlefield 1 and Valorant) and loading (Battlefield 1 took 15 minutes to launch for the first time), but once everything is installed and loaded it runs almost as good as it did on Linux.
Steps to recreate:
It won't screw up your main drive, for me Windows doesn't even recognize that there is a main drive. The only major pain point I had is that it somehow screwed up my Bluetooth, so use wired headphones.