Don't they have two teams, one working on that Capcom X... game and the other one presumably working on this project for the last two years ? It shouldn't be impossible for them to have a trailer. Xenoblade had a trailer at E3 about a year before its (Japanese) release, given that game's critical reception I wouldn't be surprised if they gave us a trailer (or short teaser).
Actually I think they've 3 teams, one working on the Wii U project, the other on the Project X game for Bamco Nandai (they still own a little part of the studio) and the last team is on another 3DS game for Nintendo.