As the creator of our universes, we have the right to reshape it as we will, but I'm currently indecisive about something in this universe. Truly, I'm indecisive when it comes to certain situations like this. The indecision for me to decide, whether a chuuni academy should exist only in Japan or not. Of course, outside of Japan, it is relatively known as THE PHASE! so it's possible to have multiple branches of the academy around world "sheltering" these potentially disastrous or miraculous daydreamers. This is an excuse for me to write some super action fight scenes with some cliche plot for fight's sake.
Technically such a power falls under reality warping. So, which of the dimwhits with a godcomplex is actually god now?
There is a limitation, and there is a system that regulates such power, but only those higher ups in the academy know of it. Let's say, the chuuni here are chuuni, but their delusions become real when they enroll as students of the academy. So their delusions taking actual form or shape with varying power scales based on their chuuni-power. Multiple god-complex chuunis don't necessarily mean they're automatically gods in the academy, which they are, but their "access: granted" is constraint by their "observation" to reality. In conclusion, they need to literally destroy their sense of reality to fully access all "levels". Those are literal people with magical affinity. The chuunis here have no magical affinity whatsoever, and are regular humans, but their delusions are used as a power fuel to materialize their twisted concept of their own reality vs everyone else's reality. Of course, the power becomes only a fact in the academy grounds, but outside, they're just base chuunis.
There actually is one such manga. The students are really heroes, demon kings and stuff. Ai-chan doesn't remember much though, because it was like over a year ago since it was last updated.