Thanks for your answer, but only find methods passing a location, a point (latitude and longitude), but my interest is to get a list of addresses in an area (defined by a rectangle or a polygon).
The online services that convert a coordinate into an address don't allow you to pass in a geographical rectangle and get all addresses within that rectangle.
I think that's because it'd be a massive drain on their resources to provide such a service.
Even a small rectangle could contain many hundreds or thousands of addresses.
So i think you'll find no-one provides such a service.