Maybe the plot would be similar to that in Soul Eater, where Kageyama and Hinata were originally meant to hunt Kenma and Kuroo down but became best friends instead??? Eventually they become great sparring partners!!!
(Also Kageyama wants to know aLL the meister skills like ALL OF THEM lmao and Kenma is a super duper strong meister so yes Kenma is senpai -thumbs up-)
(Kuroken and Bokuaka would also probably form a double team thing because Kuroo and Akaashi are both shadow weapons?? hmmmmmmmmMMMM ¯\_(ツ)_/¯)