This is a style that I created today. First, let’s see an image, then we will see the construction details.

The style is based on a Simple Watercolor filter (that is basically a Map to Palette filter with a twist) and the two different Sketch filters, all of them can be found in the Building Blocks / Simple Styles folder.
We have a normal and a saturation boosted version of the Simple Watercolor image.
The Sketch 2 is used for creating thick lines that we will blend in with reduced opacity.
The Sketch filter is also set to output thick lines, but the Majority at the end of the chain will reduce this thickness in an interesting way. The black lines on the white background will become thinner at the ends, where there are more white pixels than black ones, so they win the Majority vote for the color of the pixels in these areas.
All the sketches are of course blended on the color images with Multiply.
There is final blend, this time using the layer structure, where we Color blend the original on the filter graph result. This will give the smooth gradients that would not be present with the Simple Watercolor alone.
