Hashirama doesn't use Wood Clones like that in character, he created five for a very specific reason in the War Arc, four to create various entrances in the barrier for the Allied Shinobi and the fifth one to fight Madara, so the idea that he's going to make half a dozen Wood Clones to fight the Biju isn't supported by anything.
Also, I'm skeptical as to whether or not Hashirama could even put the Biju to sleep given that they're Edo Tensei being controlled by Obito via the Chakra Rods, and even if he can, what's stopping Obito from reabsorbing them into the Gedo Mazo and then pulling them back out again?
Hashirama has no permanent means of dealing with the Biju.
Again, speed is equalized, it took Minato teleporting away to escape, if Hashirama gets touched he isn't escaping or having time to do anything, he's not even aware of the technique either so it's not like he knows what will happen when he's touched.
I never said he can't react, I just said he can't do anything about it, which he can't, unlike Minato he can't teleport out of it.