During Superman and Captain Marvel's climactic battle at the end of the episode, Captain Marvel winds up and throws a straight punch with his right. However, in the next shot, it's his left hand that collides with Superman's face.
The core Leaguer's table changes drastically once Captain Marvel leaves the room in the second-last scene. The gap in the chairs changes Batman is now where the gap was in the previous scene, the order that the Leaguers are sitting in is the same.
While Superman and Batman are casually talking about Captain Marvel while in they fight some lesser-known villains, there's a short, but noticeable, scene where Superman's "S" on his costume is reversed.