You'd likely have to get an hourly report that shows the wall temperature, and then calculate the radiant heat transfer yourself.

I don't believe eQUEST does this. I don't know if eQUEST will even radiate on to itself if the geometry warrants it.

The only time I've seen this as a design issue is in urban areas where highly glazed buildings with reflective surfaces reflect solar radiation to another building increasing the solar gain of that building.

I would think that would be a more significant factor than long wave radiation from the surface of a building upon another building's skin.