Of course pitchers can turn spin in and out. Its the degree of spin that may not be equivalent to each other. My daughter throws her drop majority of the time. Though it is not with the same spin every time. Three locations straight and breaking in and out like a curve but down. Breaking-in they will say screw because that's the direction of the slant of spin.
The pitching coach for the college she goes to has different signs for each of her drop pitches. She doesn't get to choose which direction she wants to throw her drop, right, straight or left. Those are called using different signs.
She will throw a straight drop and
back-to-back put a twist on spin gets batters to chase and also gets her looking strikes. Very effective strategy mixed with rise and changeups.
The pitching coach for the college she goes to has different signs for each of her drop pitches. She doesn't get to choose which direction she wants to throw her drop, right, straight or left. Those are called using different signs.
She will throw a straight drop and
back-to-back put a twist on spin gets batters to chase and also gets her looking strikes. Very effective strategy mixed with rise and changeups.