Free UE 4.22 Post Process Cel Shader Project: PPCelShader (alwei)

Overview

PPCelShader is a popular Japanese sample project by alwei (Okazu of Epic Games Japan) that implements a cel/toon shader purely as a post-process material in Unreal Engine 4.22. Rather than editing every surface material, it applies the toon look in post and includes four flexible outline-drawing methods plus a demo map for comparing them, with no extra plugins required.

The roughly 21 MB repository is on GitHub under the Unlicense with a Japanese/English README and the .uproject included; since it targets UE 4.22, you will need to convert the project to open it in Unreal Engine 5. A classic reference for stylized NPR rendering and outline techniques.