What you’re asking is if you can run the existing Linux Mint on your drive within Windows running on the same drive?
Yes, exactly this. It used to be possible with live usb keys years ago, where you could boot the key normally and have a persistent live disc, but there was a Windows tool that would virtualise the key, letting you access the persistent disc from within Windows.
The reason I want to do it is for programs like Thunderbird, where you have to export your settings, email, etc. to be able to import them on the other OS. As far as I’m aware, this can’t be done by just copying files, you have to export them first.
I have memory issues, so I often forget about a program until I need to use it, and if I’m already in Mint, it means that I have to stop what I’m doing and reboot, and then lose track of what I was doing in Mint. If I can access both OS at the same time, like with a virtual machine guest and host, I can just grab whatever I need until I’ve got everything transferred over.