final effect
Step 1. Open the picture material.
Step 2. Duplicate the layer and name it "Blur Layer", go to Filter>>Blur>>Special Blur, set the radius to 10 and the threshold to 30.
Step 3. Duplicate the original layer and name it "Stroke", Filter >> Stylize >> Lighten the edges, edge width is 1, brightness 12, smoothness 15; Invert (Ctrl + I), Image > > Adjustments >> Remove color.
Step 4. Set the layer blending mode to "Multiply" and the opacity to 80%.
Step 5. Duplicate the blur layer, name it "Watercolor", invert it (Ctrl + I), and set the layer blending mode to "Color Dodge".
Step 6. Set the foreground color to black, select the following dry brush, set the brush opacity to 10%, and apply the watercolor layer to get the following effect.