Both Soaring Hawk and Sprinting Wolf feature the same story, gameplay, characters and locations. The difference is that each has its own set of spirits so to recruit all spirits the player has to trade them via Game Link Cable between the games.
Both Soaring Hawk and Sprinting Wolf have matching stories, gameplay elements, characters, and settings. The difference lies in their individual sets of spirits; therefore, trading these spirits between the two games is necessary for collecting all of them.