Basically I want to create shader with custom casted shadow in Shader Graph. For example I want to control shadow color. How can I achieve it?
You need to get the shadow in a custom lighting node.
This is a good start: GitHub - Cyanilux/URP_ShaderGraphCustomLighting: Some custom lighting functions/sub-graphs for Shader Graph, Universal Render Pipeline
I have a ready implementation in my Unity asset: https://assetstore.unity.com/packages/vfx/shaders/shadow-receiver-urp-ar-mr-directional-additional-light-shadows-228069
Damn this repo is exactly what I was looking for, thanks a lot
The URP samples also show how to do several such things, you just need to know about the shader keywords to put in the main graph (the examples have them)