If you loved Ben 10: Alien Swarm, try Ben 10: Race Against Time
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.
What they share
Both films are directed by Alex Winter, and they both carry the playful mood tag, and they sit in Action / Science Fiction / TV Movie territory. If that's the register that drew you to Ben 10: Alien Swarm, the second film will land in a comparable space — through a different lens.
playful
What Ben 10: Race Against Time is
Alex Winter, of all people, directed this. A villainous alien escapes imprisonment after being locked away for centuries. Ben must master the Omnitrix to stop him from opening a portal to his home world. It is what it is.

