So it's duel canon with the Burtonverse and Schumacherverse?The easter eggs and logic behind Patience's powers suggest so, so yes. It has also been semi-approved as part of the Burton/Schumacher universe by a review of the film on the DC YouTube channel.
If the Burtonverse and the Schumacherverse are not the same (I still think that they are the same, but whatever) then it would be part of the Burtonverse since Batman Returns is Burtonverse and none of the Schumacherverse reference Catwoman (the character, not the movie) as far as I rememberSo it's duel canon with the Burtonverse and Schumacherverse?