Batman’s Restoration of Faith: Zack Snyder’s Justice League gave Batman the best completion arc, which Zack Snyder set up in Batman v Superman.
Zack Snyder’s Batman Seeks Redemption: The film begins with the death of Superman sequence from Batman v Superman, but this time from the perspective of Lois, Bruce, and Diana.
But Zack Snyder’s Justice League is a justice done to the most important character of the DCEU storyline, Batman.
In Zack Snyder’s Justice League, Batman was the only major character whose character arc was being followed from a previous installment in the franchise, while the others were more or less in the first theatrical venture.