Did you even read the manga? Even when Hidan wasn't attacking, Kakashi couldn't get away from him.
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If Kakashi was that much faster than Hidan then he would have been able to escape from him yet he couldn't.
If Kakashi who has the sharingan and the ability to predict movements couldn't even find a way to get away from Hidan then Sasori has no hope.
Tell me how is Hiruko going to kill him, as far as I know he has nothing that could even harm him and he will eventually run out of projectiles his only way to defeat Hidan is by pulling out the 3rd Kazekage puppet but Hidan won't let him do it.
Also, Shikamaru didn't trap him in his shadow by himself, Hidan was fighting Asuma at the same time which makes it very difficult to dodge so that argument is invalid.
Kakashiw as only able to make a shadow clone due to his sharingan by finding an opening, does Sasori have good reflexes or the sharingan? I don't think so.