TextMeshFadeAlpha.cs

using TMPro;
using UnityEngine;

namespace uMMORPG
{
    [RequireComponent(typeof(TextMeshPro))]
    public class TextMeshFadeAlpha : MonoBehaviour
    {
        public TextMeshPro textMesh;
        public float delay = 0;
        public float duration = 1;
        float perSecond;
        float startTime;

        void Start()
        {
            // calculate by how much to fade per second
            perSecond = textMesh.color.a / duration;

            // calculate start time
            startTime = Time.time + delay;
        }

        void Update()
        {
            if (Time.time >= startTime)
            {
                // fade all text meshes (in children too in case of shadows etc.)
                Color color = textMesh.color;
                color.a -= perSecond * Time.deltaTime;
                textMesh.color = color;
            }
        }
    }
}