Johansson says her most odd and uncomfortable day on the movie was the time she was “riding Sebastian Stan like a mechanical bull.“I felt so bad for him — and me! They hoisted me up on poor Sebastian’s shoulders and I was holding on with my legs wrapped around. It was horrible!” Or, as Evans calls out after overhearing her answer: “Sebastian’s best day at work!” “It was terrible!” Johansson insists. “He was like ‘Ow my hair.’ I’m whipping around him and choking him out. It’s a pretty great Widow move. But that day shooting it, I was looking at the directors going: ‘I hate you…this better look good!’”” — Entertainment Weekly.
The hardest thing to do as an actor is to act without dialogue and Sebastian Stan did such an incredible job with this character, give him so much life and complexity and texture without a lot of dialogue. – Anthony Russo
He conveyed incredible menace just through movement for a good 60 minutes in the movie. And that is the hardest job in acting. It’s always very difficult to convey emotion without speaking. – Joe Russo
– Captain America: The Winter Soldier Directors’ and Writers’ Audio Commentary