Currently OneNote has not caption option for an imported image paste to page. There is however an "Alt Text" option. This option however doesn't show the caption as part of the image object.
I come from an academic background, and it will be very helpful for research related note taking I could add caption and title that will be part of the image object itself. It seems like the Alt Text option check all the right boxes, but there is no option to display the title and caption on the page! pleas make it possible.
Also, please make it fully accessible through key binding (for example in the Alt Text option it is necessary to use the mouse to click "Done", if you could use Ctrl+Enter instead it will be better.