WooCommerce Chained Products:
Chained Products is a good alternative to product bundles and composite product extension. If you are looking for a simple yet powerful solution for selling multiple products in combination, chained products are for you. After installation, you can create a combo product from any combination of simple or downloadable products. You also can chain as many products as you want.
You can give a special discount if they purchase combo rather than single products and this will enhance your selling volume. After installation, you can easily add new chained products as usual as creating simple products and later on-chain other products to them as needed or preferred.