Third Person Item Displays are not translatable between Alex and Steve Models

Due to the difference in arm size between steve (default) and alex (slim) models, when translating along the X direction in the third person display, items that are perfectly centered for one model type are off by -0.5 for the other. As there is no separation between the model types, this means that any visual differences are exaggerated the closer they move to the center.

This can be viewed in-game be creating a resourcepack with assets/minecraft/models/block/block.json looking like so:

{
    "gui_light": "side",
    "display": {
		"thirdperson_righthand": {
			"rotation": [35, 0, 0],
			// Center for Steve model
			"translation": [-6, 0.25, 1.75],
			"scale": [0.65, 0.65, 0.65]
		},
		"thirdperson_lefthand": {
			"rotation": [35, 0, 0],
			// Center for Alex model
			"translation": [-5.5, 0.25, 1.75],
			"scale": [0.65, 0.65, 0.65]
		},
		"gui": {
            "rotation": [ 30, 225, 0 ],
            "translation": [ 0, 0, 0],
            "scale":[ 0.625, 0.625, 0.625 ]
        },
        "ground": {
            "rotation": [ 0, 0, 0 ],
            "translation": [ 0, 3, 0],
            "scale":[ 0.25, 0.25, 0.25 ]
        },
        "fixed": {
            "rotation": [ 0, 0, 0 ],
            "translation": [ 0, 0, 0],
            "scale":[ 0.5, 0.5, 0.5 ]
        },
        "on_shelf": {
          "rotation": [ 0, 180, 0 ],
          "translation": [ 0, 0, 0 ],
          "scale": [ 1, 1, 1 ]
        },
        "firstperson_righthand": {
            "rotation": [ 0, 45, 0 ],
            "translation": [ 0, 0, 0 ],
            "scale": [ 0.40, 0.40, 0.40 ]
        },
        "firstperson_lefthand": {
            "rotation": [ 0, 225, 0 ],
            "translation": [ 0, 0, 0 ],
            "scale": [ 0.40, 0.40, 0.40 ]
        }
	}
}

And then running one of the following commands:

'summon minecraft:mannequin ~ ~1 ~ {"profile": "Steve", "equipment": {"offhand": {"id": "oak_log"}}}'

'summon minecraft:mannequin ~ ~1 ~ {"profile": "Alex", "equipment": {"offhand": {"id": "oak_log"}}}'

'summon minecraft:mannequin ~ ~1 ~ {"profile": "Steve", "equipment": {"mainhand": {"id": "oak_log"}}}'

'summon minecraft:mannequin ~ ~1 ~ {"profile": "Alex", "equipment": {"mainhand": {"id": "oak_log"}}}'

For the offhand mannequins (assuming offhand is lefthand), the oak log will be centered for the Alex model but off by -0.5 for the Steve model. For the mainhand mannequins (assuming mainhand is righthand), the oak log will be centered for the Steve model but off by 0.5 for the Alex model.