From the back of my head, I know there was a discussion on such a topic, I guess back in 2024 or 2025, which exactly I can not say. It was about a blue (bluish) sketch layer and inking, and I believe, among others, @Deevad and @YRH were participants of this discussion, but this can be wrong. So if you want to try our forum search on this, you should have the parameters to begin with.
Found it:
If that has what you are searching for, I don’t know, and if you need more, in the upper right is a magical tool …
