You can not pass 2 objects to and from a widget. You can retrieve the enclosing context with a mx.xas.get and passing a xpath with currentobject. See other widgets how to do that.
You can modify widgets to your own wish, but you need to build one yourself first to get used to the way they work.
You can pass the inner object to a microflow and in the microflow retrieve the 'context' over the association.