掛載在UI上的腳本：

using UnityEngine;
using DG.Tweening;
using UnityEngine.EventSystems;

/// <summary>
/// 此腳本掛載在UI上,鼠標在UI上滑動時旋轉指定對象
/// </summary>
public class UITouchRotateTarget : MonoBehaviour, IDragHandler
{
    /// <summary>
    /// 要旋轉的對象
    /// </summary>
    public Transform target = null;
    /// <summary>
    /// 旋轉速度(3-5效果最佳)
    /// </summary>
    public float speed = 5.0f;

    //DOTween過渡時間(為1時效果最佳)
    private float m_time = 1.0f;
    //緩存Vector3,避免頻繁New
    private Vector3 m_rot = Vector3.zero;

    public void OnDrag(PointerEventData eventData)
    {
        if (target == null) return;
        float y = eventData.delta.x;
        m_rot.y = -y * speed;
        target.DOLocalRotate(m_rot, m_time, RotateMode.LocalAxisAdd).SetEase(Ease.OutCubic);
    }

}

效果：

GIF 2022-10-25 20-29-50.gif