The one on Earth ages more.

For the person who moves, the circumference of the universe is smaller. So he sees his twin on Earth crossing the universe in a shorter time than his twin sees him crossing the universe in the spaceship. So at the end of the travel, the spaceship twin will say that the total time passed is less than what the Earth twin will say. Both will agree on the speed the other one was going. They disagree on the total distance and the time.