Elwynn Storyteller

Explicit support for colouring character textures during composite may not be readily available for the designers, but this is definitely not an engine limitation. They add all sorts of shaders in for spell effects (see void elves, for example), so this can absolutely be done.

I have studied the engine heavily for years to make my old works. It's not, and it can't. Yes, they can apply a cover OVERLAY to a whole model using a multply, but there is no way to specifically color only a section of a model, nor is there a way to overlap shaders.

I've also plenty of experience given that I developed wow.export. Each geoset on an M2 model can have a separate shader assigned, and they are not limited to just multiply operations. https://wowdev.wiki/Pixel_shader_logic_for_mixing_colors …

Color shading is heavily used in ADT mixing as well, and has been heavily used since WoTLK. Additionally, plenty of item components (also M2) has colour shading on effects using masks.

Also I'll add while the old tabards suffered under technical restraints, recent guild customizable assets (mount banner, cauldron, chest, etc) all use colouring shading DIRECTLY on the M2 models, EXACTLY as I've suggest for hair/eyes.

Storing new RGB values on characters is a data issue, and transmitting that information to clients is a netcode issue. Feeding colour values to a shader and rendering? Never was an issue. It's used HEAVILY already.

Hmmmm could be it's improved more since I stopped playing. Guild tabards from what I saw used preset textures per color option, just like all other armors. Any time they have mixed it's been mesh overlays, not true shaders you would find in unreal. Even skies use a mesh trick.

Yes, the old tabards were preset textures per-colour and variant, just like older character customization was. The newer guild stuff uses desaturated textures and colour shading, not even just on a per-geoset level, but a per material level.