It seems that ShaderGraph does not properly handle the case where assets (textures) used as input are stored as SubAssets in the project, when serializating the shader.
Steps to reproduce:
- open included project
- open "New Shader Graph" with ShaderGraph editor
- Assign the two textures contained as SubAssets in "New TextureContainer" to the Sample Texture nodes in the graph
- Save the ShaderGraph asset
- Select "New Material"

Expected result:
The material inspector showing the two texture properties, both with the correct, different texture applied.

Actual result:
The material shows that the first SubAsset texture gets assigned to both texture properties in the shader. It seems that ShaderGraph does not handle the case where the asset is a SubAsset properly during serialization, and can only use the first SubAsset in the container.