Drone 51 did an attempted swap awhile back. As Old Man Mavic said there are different threads and screw lengths but also that the thickness of the props at the screw holes is different. Drone 51 actually cross threaded his drone by using the longer but different threaded screws. It might be possible to get the right screw length and thread but the hoops to jump through for a marginal benefit in db rating and speed/ distance probably isn't worth it. I've heard the MM and Mini2 side by side and, to me at least, it seems more of a frequency change than an actual significant drop in volume.