If you loved Fight!! Spirit of the Sword, try Legend of Crystania: The Motion Picture
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

Fight!! Spirit of the Sword
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Legend of Crystania: The Motion Picture
What they share
Theyboth carry the epic mood tag, and they sit in Action / Animation / Fantasy territory. If that's the register that drew you to Fight!! Spirit of the Sword, the second film will land in a comparable space — through a different lens.
epic
What Legend of Crystania: The Motion Picture is
You search for a lost king in a war-torn land, but ancient secrets and shifting allegiances complicate your quest, the film unfolding against a backdrop of mythic struggle.