As a side note, I've been wishing for a plug-in that would keep the annotations separate from the code, in .pyi files, but transparently integrate them into the editor. I.e. I would write the annotations as part of the code, but on a save they would be removed from the .py file (while still being displayed in the editor) and save them to .pyi.

I would write such a plug-in for PyCharm/IntelliJ myself if I had more time on my hands. :/

and pylance uses pyright to do so.