Unfortunately I dont think you can move all the hotspots in a batch, or resize while moving the hotspot exactly however you want it to move.
If you're using MMF, however, you can just skip between frames and enter the hotspot as a numerical value rather than clicking and draging it. This is a lot faster, I think, since using a mouse takes longer than using the keyboard, as any good programmer will tell you (since you cant overshoot targets, etc).
If you really wanted you can get programs that record mouse and keyboard actions, so you could record the mouse clicking on the "next frame" button, then the keyboard typing the hotspot values and run that for however many frames you have. However it will probably take you longer to find and download the software than it would just do it by hand 8--)
"Now I guess we're... 'Path-E-Tech Management'" -Dilbert
You have to enter the first Picture of an Animation sequence. Maybe choose east direction, and then doubleclick at the first picture to enter the Picture Editor for it.
Next step is to activate the Hot Spot Button to show the Hot Spot there. Then press the ALT GR Button ( the right one of those two, below the " : " Button ) at your keyboard, hold it, and move the Hot Spot with the Arrow Buttons or by clicking with the Mouse Pointer to the destination point . The Hot Spot of all the other Pictures in this Animation Sequence will be at the same position as in your first picture now.
Note that you should do this with uncropped original pictures.
Changing the Hot Spot in this way forces all the other pictures of the Animation sequence to use the upper left corner of the picture as 0/0 . And placing it then to the same new coordinates in all of them. First pictures new Hot Spot position is at 10/10 ? so all the other Pictures will also have the Hot Spot at 10/10 now . And so cropped Animations starts to dance after this action because they have lost their real centering
For your feet in the ground problem : keep in mind that enlarging the whole sprite also changes the size between feet and upper left corner . And so your exact positioning doesn´t fit to your old x/y anymore . So why not simply change the code for that ? Easier than changing all Hot Spots ...