If you loved Scooby-Doo! & Batman: The Brave and the Bold, try The Death of Superman
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
You already loved

Scooby-Doo! & Batman: The Brave and the Bold
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The Death of Superman
What they share
Both films are directed by Jake Castorena, and they sit in Action / Animation / Science Fiction territory. If that's the register that drew you to Scooby-Doo! & Batman: The Brave and the Bold, the second film will land in a comparable space — through a different lens.
What The Death of Superman is
You fight alongside the Justice League against a monstrous threat, but then a powerful beast arrives, and the team's strength is put to the test. The film leaves Superman at the center of the battle.