BITKit/Packages/Runtime~/Unity/Scripts/Components/AutoSetLayer.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
namespace BITKit
{
    public class AutoSetLayer : MonoBehaviour
    {
        public int layer;
        void Start()
        {
            GetComponentsInChildren<Transform>(true).ForEach(x=>
            {
                x.gameObject.layer=layer;
            });
        }
    }
}