Stir baked beans, kidney beans, cannellini beans, barbeque sauce, and brown sugar together in a large bowl.
Heat a large skillet over medium-high heat. Cook and stir beef, sweet Italian sausage, and hot Italian sausage in the hot skillet until browned and crumbly, 5 to 7 minutes; pour meat mixture into a slow cooker. Cook and stir kielbasa in the same skillet over medium-high heat until browned, 5 to 7 minutes; add to slow cooker. Top meats with chopped bacon.
Pour bean mixture over meats in the slow cooker and stir to combine.