[1.20.x] Multilayer Block Rendering

[Naamah]

Hello,

I am creating am mod that adds different "compressed" versions of blocks. I am trying to get each block to have an overlay that is different on each stage of compression. The issue I have is, I don't know how to get multiple layers to work. I have the code for the block which works, but I can't figure out how to format the model/block json file to get it to render with 1 layer overlaying the other.
I have tried using something like this:

ItemBlockRenderTypes.setRenderLayer(ModBlocks.COAL_BLOCK_1X.get(), renderType -> renderType == RenderType.solid() || renderType == RenderType.translucent());

{
  "parent": "block/block",
  "loader": "forge:multi-layer",
  "layers": {
    "solid": {
      "parent": "block/cube_all",
      "textures": {
        "all": "minecraft:block/coal_block"
      },
      "transform": {
        "origin": "center",
        "scale": 1
      }
    },
    "translucent": {
      "parent": "block/cube_all",
      "textures": {
        "all": "maybecompressed:block/1x"
      }
    }
  },
  "textures": {
    "particle": "minecraft:block/coal_block"
  }
}

Which is based on the source of AllTheCompressed mod.

I also tried:

{
  "parent": "minecraft:block/cube_all",
  "textures": {
    "layer0": "minecraft:block/coal_block"
	"layer1": "maybecompressed:block/1x"
  }
}

I see that on the Forge docs ItemBlockRenderTypes#setRenderLayer() is depricated, but I am unsure of how to get around that.