MatCap シェーダー
参考：
Free MatCap Shaders | Unity Asset Store [Official]
MatcapFX | Unity Asset Store [Official]
Shader Pack – Amazing Matcaps | Unity Asset Store [Official]
MatCap Shader Pack | Unity Asset Store [Official]
MatCap Pro | Unity Asset Store [Official]
肌用 MatCap シェーダー
参考：