There's no one off the top of my head, again, it's only been 190 minutes at the U20 level that I've now seen him. But he's a traditional No. 6. Moves the ball fast, accurately, with serious velocity and confidence. In the short time I've watched him he hasn't rarely made a bad touch and it's not like he isn't pushing tempo. Decent passing range, too.
His defensive positioning is amazing, though. His awareness in his own end is freakish and his ability to read the play, anticipate a pass, pick it off, and move it into space is really impressive. However, the most impressive thing he does is cover for his fullbacks when they lose it. Argentina plays their backs really high and when they lose it, Sosa is immediately tracking runners back while still looking at the ball and getting into passing lanes extremely well. And he looks FAST when he's doing it - the attackers are not separating, he is running them down. It's really impressive.
He just looks like he's been playing that anchor man / holding mid role his whole life. He just looks supremely competent, but with all the physical attributes you'd want in that role But AGAIN, it's been 190 minutes.