I made these materials because I wanted a hand drawn outlined look, but Blender's built in tool, Freestyle, was too taxing on my little Mac. This a faster alternative.

There is an EEVEE and Cycles material. The Eevee material only works in Eevee, the Cycles material works in both. As the outline is related to the size and faces of an object, you may need to create a new material and adjust the position of the black "pin" in the first slider for smaller objects. It should be pretty clear when looking at the nodes.

The materials are obviously customizable and there are a few different variations already in the project.

CC-0 so do whatever your heart desires. As long as it's legal.