I was thinking more along the lines of using namespaces and FUSE. I'm aware that Python kinda treats them like folders transparently, but not completely for reasons (and more) that you described.
Wonder what the FUSE equivalent for windows is.
A 2016 comparison by the developer of WinFsp says WinFsp is several times faster in performance tests [1]. According to the readme for Donaky [2], since then Dokany got faster.
[1] https://github.com/winfsp/winfsp/issues/19#issuecomment-2653...
[2] https://github.com/dokan-dev/dokany/blob/255e4a508b744996191...