Emma Frost in X-Men: First Class
In X-Men: First Class, a lot of fans felt like it wasn't fair to keep showing Emma Frost, played by January Jones, as an overly-sexualized character. One of the writers of the film claimed that her outfits had become part of a running bit, but those scenes were cut for time.
Catwoman in Catwoman
Apparently, fans weren't pleased with Catwoman getting her own movie in the first place, and her costume made things even worse. Fans were expecting her traditional and iconic catsuit, but instead, they got some strappy leather outfit that did not fit the narrative whatsoever.