Place chicken breasts in the slow cooker and season with salt, pepper, paprika, onion powder, and Italian herb seasoning.
Add minced garlic and pour garlic Parmesan sauce over chicken to coat fully.
Top with Alfredo sauce, then cover and cook on low for about 4 hours until chicken is tender.
Remove chicken, shred or chop into bite-sized pieces, then return to slow cooker.
Cook pasta in a large pot of salted boiling water until al dente, drain well.
Add Parmesan and mozzarella cheeses to the slow cooker and stir until melted and sauce is smooth.
Mix cooked pasta into slow cooker, stirring to evenly coat.
Garnish with dried parsley, portion into bowls, and serve immediately.