I have an ArcGIS Pro 2.9 Addin where I would like to put overlay graphic on the active mapview, according to ArcGIS Pro SDK documentation, there is AddOverlay method on the MapView object as below:

public static IDisposable AddOverlay( 
   MapView mapView,
   Geometry geometry,
   CIMSymbolReference symbol,
   double referenceScale,
   double showThrough
)

as in:

mapView.AddOverlay(point,
        SymbolFactory.Instance.ConstructPointSymbol(
                ColorFactory.Instance.RedRGB, 30.0, SimpleMarkerStyle.Star).MakeSymbolReference());
  });

But, in the development environment, I cannot find any such ‘AddOverlay’ method on my MapView object when examining via the . operator, (I can only see ‘AddOverlayControl’ method), could anyone help where can I access this method?