Separate Color and Luma Channel Sharpening

I think this would be an interesting new feature for some of the sharpening shaders out there. Typically in film, sharpening the color channel is generally avoided due to compression artifacts or sensor noise, but that mostly isn't an issue for games. The shader would have strength, radius, clamp sliders, and color or luma channel toggles (maybe even per channel toggles, r/g/b). Just to be clear the color channel would have luma subtracted or negated, then added back ontop sharpened. Is this possible?

Would like to see it as well. It would be very nice to have one sharpening shader that could combine Contrast Adaptive Sharpening and Filmic Anamorph Sharpen (depth-based) with your idea + added this amazing Deblur shader. If possible nothing too overly complicated (too hard on fps).

That being said I was actually experiencing some artifacts issues in a few older games (lower quality skybox textures).

Sharpening chroma would have very little perceptible affect as sharpening is by nature an affect of contrast. The chroma part of an image is only color without luminance which is needed for contrast to be applied. Even if you could sharpen the chroma, the human eye is so terrible at perceiving chroma detail that most video codecs will show a half or even quarter res on the color while the luma is full res.