fantasysmp_fabric/src/main/resources/assets/fantasysmp/equipment/witherite.json

{
    "layers": {
        "humanoid": [
            {
            "texture": "fantasysmp:witherite"
            }
        ],
        "humanoid_leggings": [
            {
            "texture": "fantasysmp:witherite"
            }
        ]
    }
}