Using the same theory that if every person in China stood on a chair, then all jumped off at the same time, it would knock Earth out of orbit and kill us all. All well and good until you realize that the mass of the Earth is about 6 sextillion tons. So even if each Chinese person weight 1 ton, there would still be eight zeroes ahead of them in line, each person having to push the equivalent of a hundred million times their own weight.
In this case, the Earth is covered with tectonic plates, like a broken eggshell with eight major pieces and several more little pieces. If, by “little”, you mean immense hunks of rock miles deep.
They kind of shuffle around, slowly, each at their own pace, and when two of them collide, rock either goes up or goes down, in fits and starts, and you get earthquakes. Mostly concentrated near where plates meet.
But there just isn’t anything to force earthquakes all at once, everywhere, unless a gigantic astral body collides with Earth, and if that happens, earthquakes are the least of our problems.
It's more complicated than that. The magnetic field of the earth acts funny when there's a big earthquake. There's more to it than just two rocks colliding.