If you loved Fairy Tail: Phoenix Priestess, try Trinity Seven: Heaven's Library & Crimson Lord
A bridge between a film you've already seen and one most people haven't. Trinity Seven: Heaven's Library & Crimson Lord has roughly 3.8× fewer votes than Fairy Tail: Phoenix Priestess — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.

Fairy Tail: Phoenix Priestess

Trinity Seven: Heaven's Library & Crimson Lord
What they share
Theyboth carry the foreign gem, playful mood tags, and they sit in Action / Animation / Comedy / Fantasy territory. If that's the register that drew you to Fairy Tail: Phoenix Priestess, the second film will land in a comparable space — through a different lens.
What Trinity Seven: Heaven's Library & Crimson Lord is
A schoolboy inherits a cosmic library and a list of questionable allies. After his cousin abruptly vanishes into interdimensional voids, a demon-teacher offers three ways to patch reality, none of them safe. The real mystery may be whether anyone’s actually reading the terms and conditions.