Is it possible to have accessories access, read, use and be linked with the EA skin/face textures, even though they are on separate texture UV Maps?

In the pic provided, I tried to make a 3D eyeball, by cloning EA's eye and eyesocket meshes, and using the EA textures.
I tried using S3OC to make default replacement head/eye meshes (it would basically force ALL sims in the world to have 3 eyeballs -- great for alien saves if nothing else), before I realized I'd have to make fit/fat morphs, ones for men AND females, different age ranges, and High/Low details, and all kinds of crap, which...EFF NO.

So I wondered if I could make it an accessory instead. I could always give it its own independent textures imported into TSRW like normal, but I really liked the idea of the eyeball linked to automatically read EA's skintone/eye color settings, the way Camkitty's wolf feet do for shoes (which share EA's body UV Mapping & textures -- unlike accessories. )

(Yes, I know this is basically trying to reinvent the frikkin wheel since there's Third Eye custom makeups by Moonskin & M1ssduo that did this years ago with better results and less muss or fuss, but oh frikkin well -- YOLO. )

So, I'm just wondering if there's any way this could even be done. I suspect NOT, but figured I'd ask, just in case. :p

Okay, KosmoKhaos just asked if I could instead categorize the third eye as a Makeup, the way S-Club did for their eyelashes.
Which is a GREAT question, that I now forward to the MTS Forum Gods.

I would assume yes, but still would need to link EA's default textures to ACCs. :\

Cuz I could totally make the eyelid and eyeball meshes separate -- put the eyelid under Eyeliner so it could read the skin texture; and the eyeball under Costume so it could read the eye texture.
[EDIT] I'm gonna move the Eyeball to Eyeshadow, and see if custom lenses will override the 3rd Eye...
[EDIT] THEY DOO~!

I'm just gonna deep clone the sims' Face mesh in S3OC, import my geoms, recat the CASP in S3PE, and see what happens. :\

I'm getting somewhere, folks....

[EDIT]
I have arrived! It worked! All hail Kosmo-senpai! :lovestruc

Ok it's the weekend and silly me I decided to push my beginner's luck and make female third eyes, right? Well...!
Eff.
My.
Life.
Someone explain to me WHY the eyes look frikkin fine in Milkshape, but the second I put them on my sim in-game, some chronic ocular condition immediately turns my sims into the most cross-eyed multi-iris multi-corona effed up sclera victim I've ever seen.

This might be a shot in the dark as I have no CAS cc experience but if you need the eyeball to read the ea skin texture, would it be possible to make it in the shoe category? I realise that then the sim wouldn't have shoes/feet but maybe there's a way to get around that...

Or if there's another category that reads the skin textures? Maybe it would be possible...?
Good luck with it!