SpriteSwitcher is a component that lets you easily change textures in sprite swap based animations in Unity3D.

SpriteSwitcher.cs

using Sirenix.OdinInspector;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;

[ExecuteInEditMode]
public class SpriteSwitcher : MonoBehaviour
{
    [HideInInspector]
    [SerializeField]
    private Sprite sprite;

#if UNITY_EDITOR
    [SerializeField]
    private Texture texture;

    private Texture prevTexture;
    private void OnValidate()
    {
        if (prevTexture != texture)
        {
            prevTexture = texture;

            if (texture == null)
            {
                switchSprites = new Sprite[0];
                return;
            }

            string path = UnityEditor.AssetDatabase.GetAssetPath(texture);
            Object[] assets = UnityEditor.AssetDatabase.LoadAllAssetsAtPath(path);

            switchSprites = assets.Where(o => o is Sprite).Select(o => o as Sprite).ToArray();

            GetComponent<SpriteRenderer>().sprite = switchSprites[0];
        }
    }
#endif

    [HideInInspector]
    [SerializeField]
    private Sprite[] switchSprites;

    private SpriteRenderer spriteRenderer;

    private void Awake()
    {
        spriteRenderer = GetComponent<SpriteRenderer>();
    }

    private void LateUpdate()
    {
        if (spriteRenderer.sprite.name != sprite.name)
        {
            for (int i = 0; i < switchSprites.Length; i++)
            {
                if (sprite.name == switchSprites[i].name)
                {
                    spriteRenderer.sprite = switchSprites[i];
                    break;
                }
            }
        }
    }
}

SpriteSwitcher.md

SpriteSwitcher is a component that lets you easily change textures in sprite swap based animations.

You need to change the animation to replace SpriteSwitcher.sprite instead of SpriteRenderer.sprite.

Frames are identified by the name of the sprite, so each texture sprite must have the same name.