This match is probably one of the weirdest to imagine since despite their gimmick being somewhat similar, their fighting styles being very different.
Since this battle takes place in New Yor, for Illusoto find a reflective surface is an easy as it can get. Inside of the Mirror World, Illuso is practically immune to whatever Mysterio does in the main world.
However, I believe that's here Illuso's advantages end: Mysterio's strategy consists in staying far away from the opponent, and let the drones do the job, so basically abusing range. This will counter Illuso's strategy, which consists of getting as close to the opponent as possible and then drag them into the Mirror world.
The biggest problem though is Mysterio's illusions, which are actually pretty insane if you watch the movie: from an insider's perspective, it looks like having the whole world warped around you, and Mysterio can make fake clones of himself, which will confuse the hell out of Illuso, and if he does fall for then, it's basically game over, as Mysterio can very well hide reflective surfaces with his illusions, and then the fight becomes Illuso vs. hundreds of Aereosmiths.
Trying to bring the individual drones into the Mirror World is basically useless because A: illusions, and B: there are hundreds of them.
The only way I would see Illuso winning is if he just stays in the Mirror World and reaches the real beck before the latter can even figure out what's going on, which considering Illuso's lack of prior knowledge, his range of only a few hundreds of meters within the Mirror World, and also Mysterio potentially finding a way to get around that, I find this to be an unlikely scenario.
So I vote Mysterio via illusions, hundreds of drones, and sheer range.