Those hemp beers I've tried did not have a noticable flavor that I could attribute to the hemp seeds. If you are looking for a nutty flavor, victory, a bit of light munich or some toasted pale malt will help.
you can certainly add some hemp seed to the mash just to say you did but I don't think it's going to bring much to the game.
Now, if you live in washington, Colorado, Alaska, or California (and have any kind of medical condition whatsoever) you could add something that would add flavor.