He cant fully control
any without summoning them & removing their consciousness first.
Ninja such as Zabuza & Haku were easily able to resist full control for moments, not only that but kabuto stated himself that he needs anko to a) increase edo's binding power & b) keep the jutsu active.
Let me make a scenario for you:
The fight starts like this
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As you can see, kabuto summons them in an unconscious state, without any form of control.
This is how he controls his edos if he doesnt possess anko.
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He cant control & bind them
remotely, he can only do that with anko's body & chakra, which kabuto doesnt get to keep.
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Since he doesnt have anko to leech off of, he cant overwrite his talismins remotely, therefore he needs to be up close to change the binding.
But he cant do this in a 1v1 fight because kabuto has to do
this in order to use SM
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Therefore, his edos provide
no use to him in battle, especially if he plans on using SM. & allowing him the use of anko is textbook prep time, which he does
not get to use.
Btw, kabuto is 6th strongest, but its not because of edo tensei