If you go down the color theory rabbit hole, you might find that complimentary colored shadows look cool and natural.
Red and green, yellow and purple, orange and blue.
Complimentary colors are opposites on the color wheel.
8-bit Nintendo games would play with color palettes.
Palette swapping is used here in Ninja Gaiden 2 to animate an interesting reveal in a cut scene, on limited hardware.
I notice that the guys stand against complimentary colored walls. Same wall, palette swapped.
Ryu’s orange shoulder has a blue shadow.
I wrote a shader that simulates 8-bit style lighting.
Palettes swap based on the lighting on a surface. I can choose any colors, but it might make sense to consider color theory.