Not sure if it creates a MIDI device, but it allows using all UWP MIDI API commands in a win32 application. So I assume somebody would still need to write a driver that converts MIDI BT devices to regular MIDI devices. Not sure. Code can be checked on github, though!
Related:
https://askjf.com/index.php?q=3751s
https://askjf.com/index.php?q=3757s