Formula 407 - S1-E12
Continuity mistake: After Diana sidesteps Antonio's advances, when Wonder Woman rushes off to save Steve she's grabbed by one of the Nazis who holds a chloroformed handkerchief to her face with his right hand, but in the closeup it's in his left hand, and then it's back in his right hand.
Answer: The transformation twirling was invented for the 1970s TV series only, to explain her quick change from Diana Prince to Wonder Woman. However, it would have been nice to do a little spin homage in the movie.