This one’s pretty straightforward, isn’t it? Deku seemed like the obvious choice for a boy Goku could train (like I’ve mentioned before, Asks mentioning the Studio always tend to lean towards crossovers). Not only is he someone who would benefit from/want traditional martial arts training, but he’s also one of the boys who gets passed around the most in previous works. So I think it’s perfectly in-character for him to want some of Goku’s “Special Training”. It is interesting how Goku mentions there being lots of boys wanting that training, though. I wonder just how many he’s trained so far.