Hey, so I would write this into the story somehow, but I can't think of a single way to do so that doesn't feel wrong or contrived, so I'm just going to make this auxiliary chapter. Basically, his quirk is cursed energy and Hakari's technique, so what does that mean?
Well, because it's a quirk, it can grow and is not handicapped by the amount he is born with. But because all things cursed energy must be balanced, he will start with a small amount of cursed energy and will have to build it up over time. How small, you might ask, until he turns 8 years old, he won't be able to pop a domain.
What's more is that because of that, he can't actually get Jackpot because he needs cursed energy to perform the preview moves. If you think that's a pointless nerf, its more like a vow where in exchange for being able to grow really strong, he starts pretty weak. Also, conditional techniques like his are only as good as the sorcerer using them because they have to live until they reach that condition.
So will cursed spirits form?
Ehh no. Why? Because he is the only one with cursed energy and he is a sorcerer so he doesn't leak it.
Then what about domains?
It's a quirk, so I'm just gonna make it target living things for verse equalization. And that's just how it is.
What about AFO?
No spoilers, but let's just say it has something to do with souls and AFO can't take it.
What are the other downsides?
Honestly, nothing, plus it has the upside of being able to evolve.
Then how does that preserve balance?
Because MHA vastly outscales JJK, and it's not even close. Except for Modulo of course, so the JJK verse gets a buff.