BlueMap/BlueMapCore/src/main/resourceExtensions/mc1_20_3/assets/minecraft/models/entity/birch_wall_hanging_sign.json

{
   "credit": "Made with Blockbench by TyBraniff for Bluemaps support.",
   "parent": "minecraft:entity/wall_hanging_sign",
    "textures": {
       "wood": "minecraft:entity/signs/hanging/birch"
    }
}