OctaneForUnity does not use unity shader code for technical reasons. We have our own shaders that perform like unity.

OctaneForUnity does allow you to create your own custom octane materials
Create a new octane override material using this guide: https://www.youtube.com/watch?v=fCBi3Fb8_oQ&list ...

I am trying to write my custom shader within octane rendering.And i have known that some posts said octane only accept "standard" or "specular (setup)" of bulit-in unity shader. So i try to modified built-in shader code(eg: .cginc file, .shader file),i found that it is successfully reset in unity ...