Which one of these models could pull off playing the role of Aphrodite?

The first one. Aphrodite is the Greek goddess of love, the first one looks more Greek, everything from her skin to her eyes. It would be even more authentic if she dyed her hair brown (that's what most descriptions say about her). If you want her to look like Venus (the roman equivalent), her hair should be red. She's also curvier, that's how most of the goddesses were depicted. She's also sultry, the second one doesn't have that look, she's just, bubbly, someone I'd expect to see in a generic Abercrombie of American Eagle ad.