GUI with two axes exactly on the same position, toolbar with zoom, handle, etc.. How user can select between two axes to use toolbars on different axes?

I have a GUI where there are two axes on exactly the same position and size. The top axes are transparent. On the toolbar I have zoom, pan and Data Cursor. When running the GUI and using let's say the Data Cursor, always the axes on the top getting the focus. So it is not possible to pick a point from the axes on the bottom. The same is true - of course - for other toolbar buttons.

Is there any trick to give focus to the axes in the background?