I've just learned that beans will suffer from blossom-drop in summer's heat, so anything that keeps them a little cooler, but still provides enough light, should not be a problem. One reason people can be surprised about how much shade plants can tolerate is that even in shade, the diffused light is usually very strong -- e.g., you can get sunburned in it.

Pumpkins, OTOH, don't do very well if shaded.

Given this information, I'd plant the beans in the shadier area. With increasing hours of sunlight, six hours or more will be enough. And I'd plant the pumpkins in the sunnier spot.

Thanks anney!