CompoundTrigger for demonstration

Mono_CompoundTrigger.cs

using System.Collections.Generic;
using UnityEngine;

public class Mono_CompoundTrigger : MonoBehaviour
{
    public class ColliderInfo
    {
        public Collider target;
        public int count;
    }


    private readonly List<ColliderInfo> mAllNowStayTargetList = new();

    private void FixedUpdate()
    {
        for (var i = mAllNowStayTargetList.Count - 1; i >= 0; i--)
        {
            var info = mAllNowStayTargetList[i];
            info.count--;
            if (info.count < 0)
            {
                mAllNowStayTargetList.Remove(info);
                Debug.Log($"{info.target} <color=red>OnTriggerOut</color>");
            }
        }
    }


    private void OnTriggerStay(Collider other)
    {
        var info = mAllNowStayTargetList.Find(x => x.target == other);
        if (info != null)
        {
            //Log -> TargetStay
            info.count = 1;
        }
        else
        {
            var newInfo = new ColliderInfo();
            newInfo.count = 1;
            newInfo.target = other;
            mAllNowStayTargetList.Add(newInfo);
            Debug.Log($"{other} <color=green>OnTriggerEnter</color>");
        }
    }
}