The addon allows you to add NPR/Cartoonish outlines in one click.
Unlike Freestyle, this method works in eevee as well as cycles engine.
Edit -> Preferences -> Addon -> Install and select add_outline.py
. After its installed,
enable it and in the addon settings select the path for toon_outline.blend
.
After this, you can select multiple objects and go Object->Add Outline.
The addon will add a solidify modifier to an object with some additional settings. Then it will add a material only to this solidified section. The material will be transparent except for the edges which will show up as an outline.