Do you mean you only want to refresh the exactly area in Map but not entire map/overlay? If yes. I can see we not support that. We only support Refresh Map based on Overlay.
Based on you requirement, I think you can consider to move the refresh layer to one overlay, and then refresh the entire overlay, it should be high performance if you only refresh one overlay.
You can tell us you scenario, we will give you some advice for the design.