Successfully complete the first two star marked reward missions for any desired trial in Quest mode, but do not complete the third star marked mission. After completing the trial, the game will automatically autosave after you exit the battle results/victory pose screen. Then, replay that trial again and complete the three star mission. Once the battle win victory screen appears, do not exit the screen. Check to see which costume patterns were unlocked. If it is for a character you do not care about, immediately exit/reset the game. Start the game again and repeat this process until you get the desired quest rewards. Note: This is possible because the game does not autosave on the victory win screen and costumes are random.