Preheat an oven to 375 degrees F (190 degrees C). Grease a 3x7 inch loaf pan.
Beat the eggs in a bowl to mix. Whisk in the cracker crumbs, onion, garlic, salt, pepper, and sage. Set aside 3 tablespoons of the Swiss cheese to use as a topping, and stir the rest into the egg mixture along with the ground beef. Pack the mixture into the prepared loaf pan.
Bake in the preheated oven until no longer pink in the center, about 1 hour. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C). About 2 minutes before the meatloaf is ready, sprinkle with the reserved Swiss cheese, and return to the oven until melted.
