I think you are talking about substitution jutsu.
Substitution jutsu have nothing to do with this.
How can you even compare substitution with law's technique?
Sasuke have been using this exactly like law uses his DF of course to a lesser extent.
To put it more bluntly :
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it is exact same shit.
Law have a "room" (space restriction) where his technque can work, same as sasuke.
Sasuke have also used it the exact same way to protect himself like law did.
There is literally no difference in law and sasuke's ability except the fact law has more to offer from it than sasuke.
And Ino takes over someone's mind , this is also completely different than what law does.
He switch two people's brain, ino takes over someone's brain.
Ino gains full control over the opponent unlike law.
Ino loses control over her own body unlike law.
Again, these two are not same , they are not even close to same thing.
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^ this explains law and sasuke very well.
Circle A is what sasuke can do with his ability.
Circle B is what law can do with his ability.
Note that Circle A lies within circle B , which means sasuke have only shown a portion of law's ability, which makes sense as its not been too long since he got his ability. We are not even sure if he can do as much as law.
But ...
The point still stands, it is still a rip off.