Other mistake: Aquaman is animated with two hands and no hook for a single shot while swimming underwater at the end battle in the Arctic.
Continuity mistake: When Flash plays tag with Faust ("Now you see me, now you don't"), there is a brief shot in which he rushes at Faust - but not inside Hyppolita's palace, but in some high-tech laboratory. Obviously a shot from some earlier series, since the coloring and style are different from the Justice League's.
Other mistake: When Lex finally manages to open Batman's utility belt and spills out its contents, we see several hand grenades dropping out of the pouches. However, these grenades are standard military egg grenades, and with their size and bulk they should have bulged out the square pouches in which they had been kept - if they had ever fitted inside in the first place.
The Brave and the Bold (1) - S1-E12
Other mistake: Flash brags about having beaten Gorilla Grodd to two girls at the beginning of the episode, but then later is surprised by talking gorillas and seemingly meets Grodd for the first time.
Suggested correction: Flash never talks about Grodd. He's telling a story about Solomon Grundy.
The Brave and the Bold (1) - S1-E12
Continuity mistake: When the car crashes into the café Flash is at, you see it hit the counter and fall back down, and nothing is on the hood. When Flash asks the guy if he's okay, there's a burger on a pretty flat part of the hood. In the next shot, it's gone, and the hood is completely crumpled up.
Plot hole: Hippolyta tells Hawkgirl of Aresia's background of being born in the outside world, the war in her country and right up to her drifting to the shores of Themyscira. It would be impossible for her to know anything of Aresia's background as in part two, it's explained that the captain of the ship who saved Aresia died shortly after reaching Themyscira and therefore would not have been able to tell Hippolyta anything.
Continuity mistake: When Aresia's shown as a child in flashbacks in the ocean she goes from being barefoot to wearing black shoes in several shots.
Legends (1) - S1-E16
Continuity mistake: When we first see Music Master's car, it's mostly in the street. In the next shot, more than half of it is on the sidewalk. And then, when the cops show up, it's nowhere to be seen even though it was parked in front of the stairs.
Injustice For All (1) - S1-E18
Continuity mistake: When Trina runs to her dad, he gets down on two knees. In the next shot, when Superman and Flash arrive, he is seen kneeling on three legs.
Injustice For All (2) - S1-E19
Other mistake: Unless he escaped prison, it makes no sense for Copperhead to be in the police van with the other Secret Society members. You can see him sitting there across from Solomon Grundy and The Shade.
Injustice For All (2) - S1-E19
Continuity mistake: When Joker comes down to the basement to kill Batman, he finds the empty titanium restraints still fixed on the post. But when Batman gives him the knock-out punch, the restraints have suddenly disappeared.
Other mistake: At the beginning, when Java is filming, you can see that the image on the lens is meant to be a reflection or a mirror image, as it should be. It appears that Mason's left hand is on fire when it's actually his right hand. However, the "23" on the building isn't a reverse image.