Olga Kurylenko was so close to becoming Wonder Woman. She was one of three women who were up for the role in the last round of choices. The final three consisted of Gal Gadot, of course, as well as Elodie Yung. It's easy to see why Olga might have been chosen. She's Ukrainian, so she has that mysterious, exotic look, plus she's tough. She's been part of the James Bond and Hitman series of movies, which are heavy on the action.
The reason for not casting her came down to the fact that she was very busy. A movie like 'Wonder Woman' takes a lot of an actor's time. It's not just the shooting time and the promotion time. It also comes down to how much training comes with the role. You can't just be tough. You have to be able to ride a horse, swing a sword, and shoot arrows.