Detail this asset from Unity Asset Store: https://assetstore.unity.com/packages/vfx/shaders/hand-drawn-shader-pack-12465
But now you can download Hand-Drawn Shader Pack FREE.
Hand-Drawn Shader Pack v1.2
A collection of non-photorealistic shaders that create a variety of stylised “hand-drawn” effects, including pencil sketch, ink, pen, chalk, and crayon.
* All features work in Unity Free and Unity Pro
* Full, comprehensively commented source code
* Highly customisable – outline and fill effects can be combined to create wide range of variations
* Demo scene and 8 example materials included
unityassetcollection.com – Get all paid Unity Asset for free