isLocal 

Namespace: SynicSugar.P2P

public bool isLocal

Description 

This just return true, if the OwnerUserID is the same with p2pConfig.Instance.userIds.LocalUserId.
Local means that this NetworkPlayer is operated by the this LocalPlayer.
We write the actions for us to perform as the instance owner in this flag.

using SynicSugar.P2P;
using UnityEngine;

[NetworkPlayer]
public partial class p2pSample {
    [Rpc]
    public void SendMessage(string message){
        if(isLocal){ 
            Debug.Log("Send message");
            return;
        }

        Debug.Log($"{message} from {OwnerUserID}");
    }
}