Character Selection Screen for Multiplayer - C#

Hello everyone I'm trying to figure out how to add a glow around objects when it's highlighted by a certain player, I plan on it being a local co-op game for now.

Something similar to how Mario Kart 64 does their character selection where they would both have their own color and box

below is how I have set up character selection
using UnityEngine; using System.Collections.Generic;

public class CharacterSelect : MonoBehaviour {

 public GameObject singlePlayer;
 public GameObject multiPlayer;

 public List<charNav> charSelect = new List<charNav>();


 [System.Serializable]
 public struct charNav
 {
     public GameObject _this, left, right;
 }

void Start() { menuSelect.transform.position = menuOpt[currentSelectedItem]._this.transform.position + menuSelectOffset; }

void Update() {

if (lastMenuChangeTime + menuChangeDelay < Time.realtimeSinceStartup) { Vector2 leftStickInput = new Vector2(Input.GetAxis("360_Dpad_X"), Input.GetAxis("360_Dpad_Y")); bool leftPressed = leftStickInput.x < -0.5f; bool rightPressed = leftStickInput.x > 0.5f;

         if (leftPressed && (menuOpt[currentSelectedItem].left != null))
         {
             currentSelectedItem = GetMenuArrayIndex(menuOpt[currentSelectedItem].left);
             menuSelect.transform.position = menuOpt[currentSelectedItem]._this.transform.position + menuSelectOffset;
         }
         if (rightPressed && (menuOpt[currentSelectedItem].right != null))
         {
             currentSelectedItem = GetMenuArrayIndex(menuOpt[currentSelectedItem].right);
             menuSelect.transform.position = menuOpt[currentSelectedItem]._this.transform.position + menuSelectOffset;
         }

         lastMenuChangeTime = Time.realtimeSinceStartup;
     }

}