If you loved Fullmetal Alchemist: The Final Alchemy, try Fullmetal Alchemist: The Revenge of Scar
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

Fullmetal Alchemist: The Final Alchemy
→
Try this next

Fullmetal Alchemist: The Revenge of Scar
What they share
Both films are directed by Fumihiko Sori, and they sit in Action / Adventure / Fantasy territory. If that's the register that drew you to Fullmetal Alchemist: The Final Alchemy, the second film will land in a comparable space — through a different lens.
What Fullmetal Alchemist: The Revenge of Scar is
You hunt for answers in a world of alchemy, but a lone killer with a scarred forehead threatens everything. The Elric brothers face their darkest foe. Fumihiko Sori directs this fantasy action tale.