I would say that most of that is in the texturing, not in shaders or render tricks.
Stuff like the sumi-e tricks in games like JSRF or Okami is a camera shader and in shows like Storm Hawks and Dragon Booster, but the rest is all in the diffuse texture maps.
If you can texture by paint the maps of yourself or lightly digitally paint over already made photo-based maps for the desired effect. Or if it’s based off of a real painting, you can project the painting onto the model and fill in the rest (if the camera is moving or rotating past the painting’s view).
Does this all make sense?