If this spell is copied, the copy will not have had any colors of mana paid for it, no matter what colors were spent on the original spell.

If a card in a graveyard has in its mana cost, X is 0 for the purpose of determining its mana value.

Emptiness's first and second abilities check to see if at least two mana of the appropriate colors were spent to pay Emptiness's cost. It doesn't matter if more than two mana of that color was spent; the effect isn't multiplied.

Emptiness's first and second abilities care about what mana was spent to pay its total cost, not just what mana was spent to pay the hybrid mana symbols in its cost.