In the game, all metadata have the model of a zero metadata
In register class - ModItems:

    public static void registerRenders(){
        registerRenderMeta(energyTool, 5);
    }

    private static void registerRenderMeta(Item item, int metaCount){
        for (int i = 0; i < metaCount; i++)
            ModelLoader.setCustomModelResourceLocation(item, i, new ModelResourceLocation(item.getRegistryName().toString()+i, "inventory"));
    }

 

In ClientProxy:

    @Override
    public void preInit(FMLPreInitializationEvent event) {
        ModItems.registerRenders();
        ModBlocks.registerRenders();
    }

 

In preInit:

    @EventHandler
    public void preInit(FMLPreInitializationEvent event) throws Exception {
        ModItems.init();
        ModItems.register();
        ModBlocks.init();
        ModBlocks.register();
        ModCrafts.register();
        ModTileEntities.init();
        proxy.preInit(event);
    }

 

RegistryName of item: "ItemEnergyTool"
Path to models:

Spoiler

 

And models (Models differ only in texture):

Spoiler

{
  "parent": "item/generated",
  "textures": {
    "layer0": "meem:items/tools/energy_tool"
  },

  "display": {
    "thirdperson": {
      "rotation": [-90,0,0],
      "translation": [0,1,-3],
      "scale": [0.55,0.55,0.55]
    },
    "firstperson": {
      "rotation": [0,-135,25],
      "translation": [0,4,2],
      "scale": [1.7,1.7,1.7]
    }
  }
}

 

Client Log: fml-client-latest.logfml-client-latest.log
What could be the problem?

Registry names are supposed to be all lowercase from 1.11 on, I believe. Not sure if this is causing your problem, but it may be.