Well, they'd kind of have to completely re-do how the game uses and applies textures, so....
(I haven't seen a mod that actually does dye-ing on the PC. Yeah, I've seen mods that have a bunch of different colors of whatever clothing or armor they do, but that's just be making a different texture file (and item ID) for each color. If you know of a mod that does it, I'd like to get a link so I can check it out

)