It's hard to do color changes like tanning or clothes changes without having a visual system that allows for that, otherwise you have to draw all the possibilities ahead of time. I've seen authors create entire systems for this in Ren'py games (Witch Trainer Silver comes to mind), in which clothing items have indivual color and transparency, and each of which can have separate, specifiable color details such as stripes and trim. I've never seen such a thing for an RPGM game; most was maybe a simple alternate costume in Karryn's Prison.