There really aren't any health laws that I know of that specifically apply to freezing, except that you want to do it as fast as possible, just as with any cooling.
I also believe that you might end up with a dryer piece of meat by refrezing a previously frozen product.
When I do refreeze I usually a heavy ziplock, and try to remove as much air as possible to avoid freezer burn.
It just downright pisses me off when they thaw a product that came to them frozen. I would rather take it frozen and thaw it when I'm ready.
I have never tried freezing in water, so I don't know about that.
But I'm sure scientifically speaking, something must occur physically to meat when it is frozen.
I don't have a vaccumm sealer but if I did I would guess that would be the best way to freeze.