Brezina totaled 51 tackles, three tackles for loss, one forced fumble, and one fumble recovery across his Cyclone career.
Kuol has four years of eligibility remaining.
Bacon led the Iowa State defense with 652 snaps played in 2025.
Eskildsen had 30 receptions for 526 yards and five touchdowns in 2025.
Manske is the sixth former Iowa State player to transfer to Penn State, following fellow quarterback Rocco Becht.
Becht leaves Iowa State with 9,274 passing yards.