Match skin tones

[Dimitris360489960tu2]

I have attached two heads from different photos in the attached one. Can someone tell me a way to match the skin tones of the heads with the bodies so they look as natural as possible?

[Abambo]

Colours are best compared when they are side by side. You need to mask what you want to modify, copy temporarily parts of the target skin tone to the skin you would like to modify. It works probably best to use adjustment layers to modify the tones, or to repaint the tones (as you are in a comic-style).