Missing shadows in some games, is there a fix for this?

[mimimi]

Maybe it's an issue with this "Scaler" game and nobody else reported it yet. Can you post some screenshots in this thread:
https://forums.dolphin-emu.org/Thread-gc-scaler

And if shadows in Luigi's Mansion are broken, can you post some screenshots here?

In general shadows are likely to be depth issues from what i gather. Can you try both d3d and opengl, both with and without fast depth?