The WooCommerce Checkout Add-Ons is another WooCommerce upsell plugin. It enables you to add multiple fields and options on your checkout page, either paid or free, to increase overall order value. With this plugin, you can improve the checkout page by upselling offers such as gift wrapping, custom message option, order tips, and much more.
You can create custom fields with different options such as text field, drop-down menu, radio buttons, etc. This plugin is extremely easy to install and use.