NetworkTransformSync.cs

using Photon.Pun;
using UnityEngine;

public class NetworkTransformSync : MonoBehaviour, IPunObservable
{
    private PhotonView photonView;
    private Vector3 networkPosition;
    private Quaternion networkRotation;

    void Awake()
    {
        photonView = GetComponent<PhotonView>();
        if (photonView == null)
        {
            photonView = gameObject.AddComponent<PhotonView>();
        }
    }

    void Update()
    {
        if (!photonView.IsMine)
        {
            transform.position = Vector3.Lerp(transform.position, networkPosition, Time.deltaTime * 10);
            transform.rotation = Quaternion.Lerp(transform.rotation, networkRotation, Time.deltaTime * 10);
        }
    }

    public void OnPhotonSerializeView(PhotonStream stream, PhotonMessageInfo info)
    {
        if (stream.IsWriting) 
        {
            stream.SendNext(transform.position);
            stream.SendNext(transform.rotation);
        }
        else 
        {
            networkPosition = (Vector3)stream.ReceiveNext();
            networkRotation = (Quaternion)stream.ReceiveNext();
        }
    }
}