src/main/resources/assets/aether_legacy/recipes/diamond_gloves.json

{
  "type": "minecraft:crafting_shaped",
  "pattern": [
    "X X"
  ],
  "key": {
    "X": {
      "item": "minecraft:diamond"
    }
  },
  "result": {
    "item": "aether_legacy:diamond_gloves"
  }
}