This Unity utility provides instanced materials on-demand at runtime using Unity's built-in shaders in URP, HDRP, and the default render pipelines. It can be imported as a package by adding this git repository using the URL https://github.com/domportera/Instant-Materials.git
It currently only supports the basic shaders - Standard, Transparent, Unlit. When creating a material, you can specify if you want it to be transparent, lit, and instanced. You can also specify any hide flags you'd like.
Make sure to check out the demo scene (pictured above) for a simple example of how this can be used. Just hit Play and then check out the two demo scripts included that run the scene.