I'm starting a project where I have a couple of alien races with sex linked traits. The males will have the default green skin and black hair. Females will have the mannequin skin and brown hair. The other race is where the males will have orange skin and red hair, and the females will have emerald skin and blonde hair. Does anyone know how to correlate skin and hair in SimPE?

Hello @LadyDucky
I don't think there is a way to do this in SimPE.

For the next generation, save your game an hour or two just before the birth of the baby. If the baby is not born with the skin color of the sex of the race, quit your game without saving, then restart your game for another birth. This may take several attempts before it is to your satisfaction.
At toddler stage (or possibly child stage for the odd toddler that has no hair), I would change their hair appearance using a mirror.

Hope this helps?
Good luck with this interesting project!

Not entirely sure if it will work the way you want it to, but here's Phaenoh's tutorial: https://modthesims.info/showthread.php?t=481869 - it's more a "make 16 default skins instead of 4" kind of thing.

You can make a skin where the male textures have orange skin and the female textures have emerald skin, but it will only work from teens and up.
There have been a few skins with separated baby/toddler/child skins - I think Chris Hatch made one a while back. I have absolutely no idea where that one went, but he proved it's possible to make one. If you can't figure it out, you could make an "In-between" color for the child stages, and then they grow up with the proper texture when they get older.

As for the hair, I don't think that's possible to automate, but you can change the hair- and eyebrow colors on babies with a mod ingame (Insimenator or SimBlender, but it only works if you have Pets or above - doesn't work with lower games), and if need be you can make it genetic in SimPE, so that's an option if they get the wrong color from birth.

Thanks! I was inspired by this! https://modthesims.info/d/514012/es...n-skintone.html

If I can't correlate the hair it's okay. This is what gave me the idea for the project. https://modthesims.info/d/514012/es...n-skintone.html I'm also okay with not being able to separate baby/toddler/child skins. I don't know why the child and below stages are so difficult to mod.

By default, child and below have unisex textures for skins, while teen and up have separated textures for female/male. If you want it any different you'll have to add various resources to the file.

(I've never done that for skins, though - I'd assume it's similar somehow to adding resources for clothes, possibly also for showerproof skintones - but some items are notorious for not playing well with Bodyshop when it comes to adding extra ages/resources, and will "collapse" the ages back into one age again. No idea if skins are like this).