>>28593875Hoopa is not stronger than most Legendary Pokemon in the sense that it could beat them in a battle of power one-on-one.
Its gimmick of creating portals at will just happens to be very useful.
It's like Batman in the DC universe -- he has contingency plans for nearly every Justice League member in case they ever go rogue or need to be subdued for any reason.
Think of Hoopa's portals as equivalent to Batman storing Kryptonite for Kryptonian threats, speedforce-dampening tech to hinder The Flash, or having a Yellow Lantern to weaken Green Lanterns.
As you can see in the movie, Hoopa's strength lies in overwhelming its opponents with powerhouses that it pulled from other dimensions.
In a normal battle, if you hit Hoopa with pretty much any physical attack from a strong Attack stat, it'll go down without much trouble.
This is similar to how Batman is defenseless against inhumanly-powerful threats without sufficient preparation or calculation.
