Instincts
The first thing I notice when I watch Ozhaino Albies play is his positioning and reactions. He seems to know where balls are going and reacts to them with as quick a first step as anyone I've seen. His instincts in the field are off the charts good, and I think you'd be hard pressed to find anyone in the minor leagues who is a more natural defender than Albies. Swanson as well has natural abilities. He positions himself to make all the plays he needs to make and does a good job of getting jumps on balls. Swanson has great instincts, but it's just hard to find someone who plays like Albies.
This was exactly my observation of Albies. There were three highly-regarded defensive SS in the Southern League last year (Guerra, Jorge Mateo, and Albies) and Ozzie was the best of the three at this...he always seemed to get a jump on the ball that allowed him to be in a good position to throw. He has great spatial awareness and seems to find the right line. This will serve him well at 2B, for sure, but it's reason enough to make SS an open competition.