you can be aggressive and try hard without being wild...controlled aggression is fine...you don't want to be a door mat but you can play smart active focused foosball without giving up your natural personality
make people earn everything and try as hard as you can every second...that is aggression, it is not being crazy, loud, boisterous, animated, rowdy, or noisy
and it doesn't mean slamming rods, but it means trying as hard as you can for every loose ball weather trying to get or stop one
it means not taking naps or being lazy
you can be an introvert and a great "aggressive" player