Brown sausage in a large skillet over medium-high heat, 5 to 7 minutes. Use a slotted spoon to transfer sausage to a slow cooker, leaving drippings in the skillet.
Add onion, bell pepper, jalapeño, and garlic to drippings in the skillet; cook and stir over medium heat until tender, about 5 minutes. Transfer to the slow cooker.
Add soaked beans and ham hock to the slow cooker, then pour in water. Add basil, Creole seasoning, and pepper. Cover and cook on Low until beans are tender, about 8 hours. If the bean mixture is too watery, remove the lid, increase the heat to High, and cook until beans are creamy.
Serve with cooked rice.
