Dana Delany delivers the line "He laughs!" exactly as she did in Tombstone.
While it's purely casual, in the Finnish dub Joker says that the Phantom looks like Darth Vader. Coincidence ?
Box Office Bomb: Due to a lack of advertising, the movie bombed hard during its theatrical run. This didn't last forever, though, as a certain trope to be seen below indicates...
Reality Subtext: Andrea is named after Andrea Romano, the voice casting director for the series. The entire romance plot came about because of Kevin Conroy ad-libbing an "Oh! Andrea" after a series of grunts. It was originally intended to be Batman getting punched, but the ad-lib made it sound a little different.
Vindicated by Cable: The movie turned a huge profit when available on VHS, earning millions more than it did while in theaters.
What Could Have Been: The film was going to be completely computer generated, but that was dropped for traditional cel-animation. The CG buildings during the opening credits are an artifact from that plan.
You Look Familiar: Andrea is voiced by Dana Delany, who later became more famous as the voice of Lois Lane in Superman: The Animated Series. In fact, Word of God has stated that it was her stellar performance here that caused them to pursue her for the role of Lois in the first place. Bruce even had a brief relationship with Lois.
The fighting style Bruce was shown practicing was very close to Taekwondo, despite him calling it "Jui Jitsu". The move Andrea performed on him, however, was from Jui Jitsu.