You can't simply do that with Edo Tensei, or chakra in general. If that were the case, he would have made a lot of other people who were in there Old Man edo tensei form, young. If Kabuto really wanted to revive Madara young because his physical capabilities would allow him to excel in battle, then he would have done so for many others.
Granny Chiyo came in her old form, all hobbling like an old lady.
The 3rd Raikage was revived old and wrinkly.
Nagato was revived all old looking.
Altering their physical state to make them younger and more physically fit would have benefited them just as much as it would Madara.
And there theirs what I said above. The soul takes the form of a hosts current physical appearance, so if the soul leaves the body then it is permenantly stuck in that physical appearance, which is why everyone who was revived with Edo Tensei came back looking exactly as they did when they died. It isn't at all possible to mold the physical apperance of a soul to your liking, so therefore if Madara died an old man and his soul was in the form of an old man, than when his soul was attached to a body for edo tensei, then he should have been revived with the physical appearance of his old man state.
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