Centering meshes inside glTF complex scene

I need to center the geometry of each mesh of grouped (n-levels) models, coming from glTF files (I want to implement automatic scene explosion).
But of course I have to maintain nodes world positions.
I tried:

    scene.traverse((node) => {
        if (node.type==="Mesh") {
            let center = new THREE.Vector3();

but it doesn’t seems to work (nodes are misplaced).
Any suggestion is welcome.