Making custom shader using nodes or Custom Node


I’m trying to make my own custom shader using material editor and/or HLSL.
As I know, there is no way to make custom shading model by plugin. We do not want to edit the engine at all (as it will make it harder to update an engine and use for other team), so we need to do another approach.

The only way I see is to make custom shading using Unlit material. It is possible to make custom lighting using Material Param Collection, but I want to use true unreal lighting data, such as lightmaps, cascades shadows, light sources location and information. I did not find any way to get lighting information using material nodes.

So, the only thing left is Custom Node, which allows me to add custom code. Is it possible to get lighting information using Custom Node? At least lightmaps. Did anyone here used Custom Node to create custom shading or managed to get information about lighting?