The names of three of the four main heroes of Final Fantasy II
(Frionel, Guy, and Leonheart) were changed to Firion, Gus, and Leon. Most town names were also slightly changed.
The Wonderswan Color re-release features much better graphics and slight changes in gameplay system (for example, the characters target the next enemy automatically in battles). This release is nearly identical to Final Fantasy Origins
for Playstation (of course, it doesn't have the CG intro).