Oh man. If only I could have a skill that allowed me to cure people's inability to control their hearing.
(Congratulations, you have learned the ability Body Modification EX)
I wasn't arguing that he would impart skills on them. I'm just saying he can pull a skill out of his bum that allows him to do ridiculous things on people. Like Mana Manipulation. Greater Recovery Magic. Whatever skill would allow him to make changes on someone else on a permanent level. Which isn't that hard.
I mean, an attack skill is already an ability to enact permanent changes on another living being, typically by making them not living. And recovery magic is typically to prevent the status of not living or to recover damage. So it wouldn't be so far fetched for him to be able to gain an ability to correct other people's issues. Like say these issues these girls have are actually curses and not an actual skill. Well why not learn the ability to Purify, and suddenly wham bam, their curses are gone.
Well, their "curses" are just side-effects of their powers they got from birth. So "recovery" magic wouldn't work on Shino, since she is "healthy". Having a really sensitive ears is not an ilness, so it wouldn't really work that was imo.
Also, with "Body modification" thingy. For that he would need to "think really hard" that he wants to change that part about them, but what if they don't want that? What if that "weakness" in some scenarions is actually benefitial to them in most of other situations? (Like with Shino's sensitive hearing. She struggles with places that generate a lot of noise, but while on adventures, she can easily hear enemies approaching 'n such. As for 'Ice Princess', the only way for her to be freed from her problems is either master her skill, which mc can only assist with his anti-ice skills, or just... scaling down the power so she can control it, which would make her weaker)
Well, in the end, It's just all speculation. What will happen in future chapters only time will tell