For best results, microwave eggplants one at a time. They will take about 6 minutes each to cook, so when making three eggplants allow sufficient prep time.
Place one of the eggplants in a microwave-safe baking dish. Pour water into the bottom of the dish to a depth of 1-inch. Pierce the top of the eggplant in several places with a skewer, no more than three-quarters of the way down. (You do not want to pierce the bottom of the eggplant’s skin.) Loosely cover eggplant with plastic wrap and microwave on HIGH for 6 minutes. (If your microwave does not rotate the baking dish automatically, rotate the dish after 3 minutes cook time.)
Carefully remove eggplant to a cutting board. When the eggplant is cool enough to handle, slice in half, taking care not to remove the stem. Gently scoop out pulp into a bowl, leaving the bottom and sides of the skin intact. (If your eggplant has an abundance of seeds, go ahead and remove some of them, if you like. Once cooked, however, the seeds will be soft.)
Transfer the shell to a baking dish that has been lightly greased with olive oil. Repeat process with the remaining eggplants and reserve.
Heat vegetable oil in a large skillet, over medium heat. Sauté vegetables until softened. Add garlic and Italian seasoning, cooking briefly. Add eggplant pulp and cook for 3 minutes more, stirring once or twice to blend. Add shrimp to skillet, cooking just until shrimp turn pink. Remove from heat, cooling slightly, then stir in parsley, breadcrumbs, eggs and cheese, combining well. Season to taste with freshly ground pepper. Gently stir in crab, taking care not to break up lumps.
Heat the oven to 350 degrees. Divide stuffing mixture among reserved eggplant shells. Sprinkle tops with additional grated cheese and dot lightly with olive oil. Bake for 10 to 15 minutes until heated through and lightly browned.
Top eggplants with marinara sauce for serving, as desired. The eggplants are also good served with a side dish of pasta. A salad helps to complete the meal.