Penn State continued to make quick work of EIVA conference opponents, sweeping Harvard for the second straight day.
Travis Luensmann recorded a season-high 10 strikeouts in his relief appearance on the mound.
Mitchell is the second cornerback to join the class.
The Nittany Lions rebounded from their latest setback in dominant fashion, beating Harvard in straight sets on the road.
Cottrell has committed to Penn State after earning a preferred walk-on offer in January.
The two seniors' reported decisions to enter the transfer portal come less than a week after the Nittany Lions' elimination from the NCAA Tournament.