Captain America and Sharon Carter From Captain America: Civil War
For Sharon: Since she's an agent of S.H.I.E.L.D., wear a professional pair of black trousers and a light blue button-down. Feel free to add a blonde wig and a gun holster.
For Captain America: Since he's such an iconic character, just pick up his trademark costume (you can always just wear a t-shirt with the Captain America logo on it, too!).