Mario Tennis: Ultra Smash
Could be related to bug #517.
In the Sand Court, ball hits are supposed to leave a mark. Cemu renders it as a semi transparent rectangle. You might need a save game to access that court, I used this one for my testing: https://gbatemp.net/threads/wii-u-save-files-compilation.427761/
When two characters (on opposite sides of the court) pick up the Mega Mushroom, there's a lot of texture flicker, with enlarged charachers going completely black occasionally. Could be related to lighting caused by one of the effects in the scene.
Tested with and without graphics packs, on cemu 1.25.4 and 1.25.5b