This is the viewing order for the DCAU
DC Universe Animated Original Movies
The DC Universe Animated Original Movies (also known as DC Universe Original Movies) are direct-to-video film projects being created by Warner Premiere, Warner Bros.
https://en.wikipedia.org/wiki/DC_Universe_Animated_Original_Movies
Justice League: The Flashpoint Paradox - resets timelines and combines them into one and
Justice League: War - is the new beginning to a new timeline (animated films based on The New 52 continuity).
Else World Movies
-Batman: Assault on Arkham
-Justice League: Gods and Monster
-Batman: The Killing Joke
-Batman Gotham By Gaslight
CW Seeds Constantine: City of Demons, dose not follow Constantine from Arrowverse. Instead it is the Constantine from JL Dark movie. But maybe later they will connect it to Arrowverse somehow.
Batman movie set
List of Movies
Films and TV-series
Reaping only the best
DC Animated Universe
by Aaron Browne