minecraft-assets/assets/minecraft/models/item/handheld_mace.json

{
    "parent": "item/handheld",
    "display": {
        "thirdperson_righthand": {
            "rotation": [ 0, -90, 55 ],
            "translation": [ 0, 4.0, 1 ],
            "scale": [ 1, 1, 1 ]
        },
        "thirdperson_lefthand": {
            "rotation": [ 0, 90, -55 ],
            "translation": [ 0, 4.0, 1 ],
            "scale": [ 1, 1, 1 ]
        },
        "firstperson_righthand": {
            "rotation": [ 0, -90, 25 ],
            "translation": [ 0, 3, 0.8 ],
            "scale": [ 0.9, 0.9, 0.9 ]
        },
        "firstperson_lefthand": {
            "rotation": [ 0, 90, -25 ],
            "translation": [ 0, 3, 0.8 ],
            "scale": [ 0.9, 0.9, 0.9 ]
        }
    }
}