As far as I understand there is no direct conversion possible with App Inventor.
You can try this example; that is graphical and uses two lists. You could just as well make these Lists of images and use the Images in the Buttons and an Image instead of a Label.
arabic.aia (5.2 KB)
Unfortunately, the Text component can not generate Arabic characters from Unicode (example U+660 to render an Arabic zero character)
Wait a while, someone might have a better solution.
Regards,
Steve