I was having a play with the very versatile Utility shader assigned to a head mesh and accidentally came up with something that looks like a pencil sketch style. I scaled the head down in Z so that it’s almost flat. The Utility shader’s ‘Overlay Mode’ is set to Wire so that the wireframe of the mesh is visible and lowered the Opacity to 0.1 (remembering to disable ‘Opaque’ and ‘Cast Shadows’ on the mesh).

Below are in camera renders from Arnold (no post processing involved).