Cook sausage in a large pot over medium-high heat until cooked through and completely browned, 5 to 7 minutes. Drain and discard grease.
Cook and stir onion with the sausage until translucent, about 5 minutes. Add squash and garlic; cook and stir until the garlic is fragrant, about 1 minute more.
Pour chicken broth, white beans, and diced tomatoes into the pot; stir. Add spinach, red wine, and Italian seasoning; bring the mixture to a simmer and cook until hot, about 15 minutes. Ladle soup into bowls and garnish with Pecorino-Romano cheese to serve.