On walking distance from Irides, by the sea towards Souvala, you will find the beautiful St. Sotira church. It is a typically Greek little church; whitewashed with blue doors, and right on the water. The sunset here is amazing, and will transform your ceremony into a scene that no one will ever forget. The light is magical, and your photos will be as well.
You will find St. Apostolos a couple of minutes north of Aegina town. It is a beautiful little stone church next to the sea. Since it is really small, most ceremonies are held right outside the church, where you are surrounded by sea on three sides. In front of the church is an old whitewashed lighthouse, which makes for great photo opportunities.