For instance, in “Nutcracker,” the script initially had Barbie as Clara stumbling when she carried a tray and catching herself before spilling it contents. But a meeting of the film’s producers and Mattel representatives led to a change because, Sheridan said, “Barbie would never stumble.”

Another time, when she was recording the scene in which Clara confronts the Mouse King, a Mattel representative asked if Barbie could sound less angry. “Because Barbie would never be angry, even confronting the villain,” she said. “She was always kind, clever and brave.”

The reins had loosened, she said, by the 16th film, “Barbie and the Three Musketeers,” in which an athletic, ambitious Barbie engages in sword fights. The studio, she said, realized people actually wanted to relate to her.

“She was able to be more silly and goofy and to have more comedic moments,” she said.

By the career-focused titles of the mid-2010s, Barbie had shed her princess gowns for pants. Now, she…