The cv2/__init__.pyi defines several type aliases that are invalid because they refer to themselves. This leaves them Unknown.

Here are a few examples:

VariationalRefinement = _mod_cv2.VariationalRefinement
VideoCapture = _mod_cv2.VideoCapture
VideoWriter = _mod_cv2.VideoWriter

Since _mod_cv2 refers back to this same type stub, these are effectively equivalent to:

VariationalRefinement = VariationalRefinement
VideoCapture = VideoCapture
VideoWriter = VideoWriter

Pyright correctly flags these as errors in the stub. They should be fixed.