Fire Emblem 4 Houses (FE3H x MHA)

In this story, Izuku will be born in the house of Yagi's along with his older twin sister Izumi. Izuku will be like Byleth in the Fire Emblem series. Inko Yagi and Toshinori Yagi (Queen and King of Faltur, land that is in between the alliance and Kingdom) after discovering Izumi contain the family crest of Yagi and Izuku held a mysterious Crest, they decide to focus on Izumi to be head of the family and abandons at the age of 8 Izuku calling him a freak and a mistake.

Izuku drops the Yagi name and joins up with a mercenary group that was lead by a man named Captain Jeralt. There he meets a kid around his age named Aaron (OC) the two boys became fast friends and ended up being brothers at arms. Jeralt also took the two boys as his own raising them and teaching his ways to them. Now the story starts like how Fire Emblem Three Houses.