Preheat oven to 375°F. Cook lasagna noodles in salted boiling water until al dente; drain and lay flat.

Melt 1 tbsp butter in a skillet over medium heat. Cook shallot, then shrimp and scallops seasoned with salt, pepper, and red pepper flakes until shrimp are pink, about 3 minutes. Stir in crab; set aside.

In the same skillet, melt remaining 1 tbsp butter, whisk in flour and cook 1 minute. Whisk in wine, then cream and garlic. Simmer until thickened, about 4 minutes. Season and add lemon zest.

Mix ricotta, ¾ cup mozzarella, ¼ cup Parmesan, lemon juice, and parsley. Fold in seafood mixture. Spread ½ cup sauce in a 9x13 dish. Spoon filling onto each noodle, roll up, and place seam-side down. Top with remaining sauce.

Sprinkle remaining mozzarella and Parmesan on top. Cover with foil and bake 20 minutes. Uncover and bake 15 minutes more. Broil briefly if desired. Rest 5 minutes, garnish with parsley, and serve.