A Season Pass—which will include all nine upcoming Ninjutsu Special Training sets and a special Jiraiya costume for avatars—is on the way for ¥2,980 (about $27).
A Ninjutsu Special Training No. 1 DLC set is on the way for ¥398, and it grants access to a playable Jiraiya.
The latest issue of Jump had some more info on the recently-launched Naruto to Boruto: Shinobi Striker game.