Enable human eyes for aliens

After having my alien sim have twins with a human, I realised that the alien-skinned, human-eyed, babies created were classed as humans. Which I'm not exactly fond of. I'd rather have human eyed aliens than green skinned humans. I would love to be able to make the human eyes available as an option in CAS for aliens but I don't know how to do it.

For the human eyes and alien eyes, I use default replacements by tainoodles, and I tried enabling the default human package for aliens but it didn't work and I also don't think it will work because the file is an override and not the eye file itself.

How do I enable human eyes for aliens without breaking my game?