Madara was highly feared because of his strength. Controlling the kyuubi and PS is enough to make fodders crap themselves.
That wouldn't be enough to cause that kind of fear.
What did Madara do to cause Hashi to backstab him?
When someone trying to destroy the village and legacy he protect, he will not hesitate to kill them even if they was his close friend
Did Madara destroyed the hidden leaf village?
Never
Did Madara Killed Hashi's children?
Never disclosed by Kishi
What made all 5 villages feared him?
His might and battle prowess