It's interesting you say that, because in the opening scene of the film Amadeus, Mozart is flirting with a young girl. I don't think it is the intention of the film director to link Mozart to AS. The film is more about the duality of human nature. The central character in Salieri has power, position as Austrian court composer and adulation of the public, but he doesn't possess Mozart's talent, so he has to crush him. Having crushed him he can't live with himself so he tries to commit suicide. This has appeal to the film director, Milos Foreman, who grew up under communism, which crushes the human spirit.
Coming back to your point, there's lot of evidence that Mozart had AS, but I don't think you'll find it in either the play Amadeus or the movie. As for Beethoven, there's a lot of speculation he had AS. Maybe one could argue that Beethoven, like Einstein, had some austistic traits and leave it at that.