"If"? Why don't we just look at what they've done on the field and you'll see a guy who is actually THRICE the player. And it ain't Bellinger pal.
In the past 3 seasons, Kiermaier has been worth 5.1 WAR in 234 games. Bellinger has been worth 2.1 WAR in 295 games.
So on a per game basis, going all the way back to the beginning of this DECADE, Kevin Kiermaier has been worth 3x the amount of WAR.