midoriya doesn't knit right now, but the next time he breaks his hand he'll have to work to get his manual dexterity back up to what he's used to. his physical therapist will give him a bunch of different exercises to try, but in the end the one that sticks for deku is going to be knitting. it won't be -- he won't ever really get good at it. he'll start to get better at managing his tension, and then he'll hurt his hand again and it'll be right back to the beginning. but... he will be able to feel the yarn between his calloused fingers and focus and count, and breathe. it will start as physical therapy; it will end up being more.
he will knit lots of lumpy hats in his friends' pro hero colors and wear them proudly. every year he'll auction off a hat handmade by the pro hero deku for charity.