I was more overpowered than the hero, so I hid my power!

"Ever since I was a child, I've loved the 'normal and light-looking but hides his strong powers' type of character. And then, a chance for rebirth came! "What would you like to be in the new world?" they asked. "I want to be someone who hides their true powers and strength!" ...But I didn't mean it to be like this!?"