Linux

It's gonna be way less hassle to just use Linux. The gaming situation is so vastly improved from 6 or so years ago, and the vast majority of games just work, with a large amount of the rest only needing minor tweaks.

The big exceptions are in competitive gaming, and even there it's pretty much limited to proprietary & intrusive anti-cheats that I wouldn't have installed on my Windows computer anyway; Riot's Vanguard and FACEIT are probably the two big ones. Also Fortnite -- even though EasyAntiCheat does work fine with Linux, Epic has chosen to explicitly not support it. If you do play one of those few games -- or use other proprietary software like the Adobe suite that also won't work -- a dual boot should be fine, it only takes maybe two minutes to swap over and unless you have two beefy GPUs you'll be limited in a KVM setup.

About the second point, your pc shouldn't be putting any resources towards a VM if it isn't active. Just shut it down, close it, and play games on your host as normal.

One more thing, I'm assuming you're doing your gaming on Steam. Check ProtonDB for all of your games to see if they work on Linux (protondb only lists steam games, so if you have games as well, I've found a google search usually does the trick). You might find that you don't even need a VM

Unless you play games with intrusive anti cheat pretty much everything works flawlessly on Linux.

I moved to arch permanently (been using Linux for other stuff and on my laptop for ages) after nvidia finally sorted their wayland support back in spring and I haven’t had a single game not work for me

It behaves like 2 computers. I have mine set up to change my input from 3 monitors to 2 monitors when the VM starts with qemuhooks by running a xrandr script. You can position the 2 monitors virtually wherever you want. qemuhooks executes another script when it shuts down to switch back to 3 monitors. (Arandr is a great gui to set up the monitors the way you like them and then save the setup as a script)

I have 2 mice and 2 keyboards. Gaming one is just the left half of a split keyboard. The gaming mouse and gaming keyboard get passed through automatically on VM startup.

You can use one kb and mouse on both the host and guest but need to manage switching back and forth with keybinds. There are probably other solutions that I am not aware of maybe ones that let you move the mouse in and out of the virtual machine.

I really like this setup though since I can have a web browser, discord, music etc open on the host and can just switch kb/mouse to control them and don't need to worry about switching the input back and forth or cycling focus (alt tab etc.) the way i would if I was not using a virtual machine.

If I want to use the mic in game and also on discord I pass the mic through to the guest and just run discord in there.

I liked the setup so much that I installed a Linux VM. Eventually everything I was playing worked on Linux and I didn't need windows anymore so I got rid of it but still use the passthrough.

I have a w11 KVM + nvidia card, even bypassed EAC when it detected the VM and refused to start

I use my iGPU in the Linux host and it's fine. I only game in the VM for lots of reasons. You can swap them but I don't have experience with that

The mic if you add it in VM hardware as passthrough USB will work on your host until the guest boots then it only works on guest.

For multi monitor just try and ask if you have specific problems

One tip is setup sunshine on your VM so you can quickly jump in from any moonlight device. Looking glass Is better but only works from the host pc

Lmk if you have other questions

eh games work fine in linux now and the ones that dont, will usually not work on vms either

Maybe it's too fancy and difficult for you. Take a look for moonlight + sunshine, parsec and their competitors.