Bring a large pot of lightly salted water to a boil. Cook lasagna in the boiling water, stirring occasionally until cooked through but firm to the bite, about 8 minutes. Drain. Pat noodles dry with paper towels.
Cook and stir ground beef in a skillet over medium heat until browned and crumbly, about 10 minutes; drain excess grease. Stir water and taco seasoning mix into ground beef; cook and stir until thickened, about 2 minutes. Remove from heat and let meat cool.
Preheat oven to 400 degrees F (200 degrees C).
Lay a noodle flat on a work surface and place 1 tablespoon seasoned meat at one end of noodle; roll up just to enclose meat filling. Place 1 to 2 tablespoons shredded Mexican cheese blend onto noodle and roll just to cover cheese; sprinkle a few black olives on noodle and roll noodle to the end. Repeat with remaining noodles.
Pour enough spaghetti sauce into a 9x13-inch baking dish to cover the bottom; lay rolled noodles with seam sides down into dish over sauce. Spread taco sauce over noodles and spoon remaining spaghetti sauce over the top. Scatter any remaining meat sauce over the rolls and cover dish with aluminum foil.
Bake in the preheated oven until the sauce is bubbling and cheese has melted, about 40 minutes. Serve with sour cream on top.