As the principal of a school for heroes, manage the school, nurture and train your students, then send them out to do whatever it is the game asks you to do! The PS4 EU version will launch on September 28, 2018, followed by October 2, 2018, for the worldwide launch for the other PS4 Regions, Switch and PC.
Source: N4G PC Valthirian Arc: Hero School Story Coming to PS4, Switch and PC with eyebrow raising launch date.