Pat the scallops dry. Season with salt and pepper. Heat 2 tablespoons olive oil in a large skillet over medium heat. When the oil shimmers, add the scallops and sear on both sides until browned, about 2-3 minutes. Add the butter, lemon zest, garlic, and crushed red pepper flakes. Cook until the garlic is fragrant and the scallops are opaque, about 3-4 minutes. Remove from the heat. To make the dressing. Combine the remaining 1/4 cup olive oil, parsley, oregano, basil, green onions, olives, vinegar, and lemon juice. Add the feta and gently toss to combine. To serve, plate the scallops and spoon over the feta and dressing. Season with flaky sea salt. Serve with crusty bread.