NetworkIdentityReference.md

Use scriptable object to refernce object. This doesn't require the object to have spawned, you can just listen for the OnValueChange (and check if value is already set)

Reference

[CreateAssetMenu(fileName = "NetworkIdentityReference", menuName = "Component Reference/NetworkIdentity")]
public class NetworkIdentityReference : ScriptableObject
{
    [SerializeField] NetworkIdentity _value;

    public event Action<NetworkIdentity> OnValueChange;

    public NetworkIdentity Value
    {
        get => _value;
        set
        {
            _value = value;
            OnValueChange?.Invoke(_value);
        }
    }
}

Set Reference

public class SetLocalPlayer : NetworkBehaviour
{
    [SerializeField] NetworkIdentityReference _reference;

    public override void OnStartLocalPlayer()
    {
        // don't destroy player objecct when changing scenes 
        DontDestroyOnLoad(gameObject);

        _reference.Value = netIdentity;
    }
    public override void OnStopClient()
    {
        if (isLocalPlayer)
        {
            _reference.Value = null;
        }
    }
}

Example use of reference

public class UIManager : MonoBehaviour
{
    public NetworkIdentityReference localPlayer;

    void Start()
    {
        localPlayer.OnValueChange += localPlayerChanged;
        localPlayerChanged(localPlayer.Value);
    }

    private void localPlayerChanged(NetworkIdentity obj)
    {
        if (obj != null)
        {
            // setup here
        }
        else
        {
            // tear down here
        }
    }
}