SSJ2 Gohan (Cell Saga) vs. Two SSJ2 Gohans (Buu Saga)

v

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CS Gohan at his peak, uninjured.

vs.

2 Gohans (when he faced Dabura; pre Z-sword, pre-Mystic)

... I'd still give it to teen Gohan, honestly. Adult Gohan is the master of scrubs.

Teen Gohan wins.

He was a LOT more powerful than adult Gohan, and in the world of DBZ numbers are irrelevant -- a team of significantly weaker beings cannot defeat a more powerful opponent: