Square Enix has announced that Final Fantasy: Crystal Chronicles Remastered will not include support for offline or local multiplayer, and will instead be limited to online for development reasons. They went with online support rather than offline so that more people have the chance to play, since they apparently didn't have the resources for both? Check out the exact statement (Google translated from Japanese) below!
As we have introduced in official broadcasts, this product does not support offline multiplayer. For development reasons, it is necessary to select either offline or online, so we selected online multiplayer so that more people can play.