Mask Of Phantasm had some pretty intense scenes, and there was blood and murder, and it implied sex so it was definitely stronger in it’s depiction of violence compared to regular BTAS episode. And definitely not exactly a kids flick despite its rating.
Long Halloween Part 2 was rated R, I believe. The first part was rated PG-13.The only R rated Batman film, animated or otherwise, was The Killing Joke...and it didn't do well critically and commercially it was only middle of the road in comparison to the other animated Batman features