Based on a list I found in 2017 that also includes the various DCAU comic series too. Those won't be on here, though.
The following series/movies are not canon and should be skipped if desiring a purely canon DCAU experience:
Batman: Mystery of the Batwoman
Superman: Brainiac Attacks
Batman and Harley Quinn
Justice League vs. The Fatal Five
Teen Titans (whole series)
Young Justice (whole series)
Legion of Superheroes (whole series)
All animated shows based on characters from DC Comics.
The official DC Animated Universe in a somewhat chronoligal order. Infos taken from all over the web. I tried to order some episodes differently, as you can see with Batman TAS' Two-Face 2 Parter - which is now separated by a couple of episodes, as the second part states that there were 6 months between the events of the two.
Watching Order: DC Animated Universe (DCAU)
by GrendelCrusherVIP 6