Wow, great think. I found out about WinFsp whilst using Cryptomator, and it immediately occurred to me that it could probably be used to implement a restic mount on Windows. I’m glad someone actually did it!
However, if you are a Total Commander user, you do not need to install anything at kernel level on your system and can make use of the recently created Total Commander plugins, which only require the standard restic binary and run entirely in user space. It was announced in this forum too: Plugins for Total Commander and Yazi