Resetting Imperial Agent Main Quest "Hero of the People"

Sadly, there is nothing that can be done here. Once a quest is completed it is completed and the choice is recorded within the system. 

The old Storyline can not be repeated like the chapters in KOTFE and KOTET and there is no rewind on this.

If you really want to experience the other parts, you will have to level up another Agent and choose a different option in the end.

Sorry to be the bearer of bad news here, but sometimes choice does matter 🙂

~Kat