Script-Fu -> Palette Knife
This is a non-adjustable script which can render a palette knife texture to an image. It does, however, render onto a separate layer, so the results can be "toned-down" as needed. (See lower example)
Original ImageDetail from "the Lovers" by Pablo Picasso
to adjust results of palette-knife script
Since palette-knife creates a new layer and leaves it --
you can adjst the layer opacity to tone the effect down as needed. You can choose from the image menu:
WINDOWS > DOCKABLE DIALOGS > LAYERS
(or Ctrl + L)
There you can set the layer opacity. In the example I drag the slider to 50% . . .
the "palette Knife" layer was already selected.
opacity set to 50%
You also need to copy the following file into presets: