All players have to go through the NCAA clearing house. My son plays D2 water polo with many foreign (mostly Serbian) players on his team and on opponent teams. He also swims. The eligibility rules are less stringent (but not hugely) for D2 with respect to math and language credits, which is why some D2 powerhouses in some sports (like Queens University and West Chester University in swimming) have so many foreign athletes that would otherwise be swimming at D1s. That said, there are no special rules for foreign athletes that makes them easy to get in from what my son's two coaches have said.