What is the difference between Sasori's Puppets and Edo Tensei?
A puppet is handmade and has no brain. It needs to be in close/mid range of the controller so that it can be controlled with chakra strings.

On the contrary, people reanimated by Edo Tensei are conscious, unless you bind their mind like what Kabuto did.
They can also move freely and have their own will to do whatever they want.