Trick

i'm not up to that section of the manga BUT i did draw tgem.. hopefully i got it right

I’d say kuni basically just replaces kazui & doesn’t use the Kurosaki surname for his own protection if this makes sense. I think that when he was younger he really loved the Shinigami but as he aged he had a much larger passion for soccer and primarily pursued it instead. While I do think that Ichigo would kinda pass the mantle of substitute Shinigami to kunigami, I’d say he (at first) was very lax on his duties 😢

Stemming in with his zanpakuto controlling him I think that his ego death + what else was going on in wildcard (probably straight torture) would force his hollow out to ‘protect him’ in a sense. So the reason his behavior differs is not only bc of trauma but also because it’s just not the same guy. I think Ego would do this on purpose bc I think that in the context of the crossover Ego would kinda be like Urahara but evil. So to shape Kuni into Noel Noa clone he figured he’d need to force the hollow in him out somehow.

I’m just yapping thoug. I don’t know enough about blue lock YET to actually write this but I am very intrigued by the idea🤔