I Can See Your Combat Power - Chapter 688 - 684: The Ambition of the Swan

This is the story of a modern sailor who was accidentally reborn as a soldier of the Brazilian Expeditionary Force, and finally became the largest plutocratic family in Brazil by virtue of his foresight.

- Description from novelbuddy

A man reincarnates in the body of a boy who suffered a tragedy, only to realize that he is in the world of My Hero Academia. What's even stranger is that his quirk seems to have the abilities of Nen and Haki.

Six years ago, he disappeared silently! After six years, he becomes the unparalleled "God of War" and returns with glory, only to find that he has a daughter whom he never knew of. Looking at his wife and his daughter, he says, "In this lifetime, I'll bring you the greatest honor and glory!”

Meloni is just a musician. A normal, charming girl whom everyone loves and admires. But she has a secret; she can manipulate sound.For years, she managed to live with that secret, until everything came crashing down when her resonance was picked up by local organizations.In the midst of all the chaos, whether she should live as an awakened conduit or just a normal person, she ends up rescuing a small black bird.But that bird, is someone the whole world is afraid of.