Hello there,
Thank you for expressing your interest in our services.
Our core plugin, “Back In Stock Notifier for WooCommerce,” provides numerous functionalities for notifying customers, including success subscription emails upon successful subscription and in-stock emails when a product is back in stock, all of which are available in the free version.
However, our premium add-ons offer additional features to enhance the core plugin and are exclusively available in the Pro version. For more details, kindly refer to our plugin’s description page on WordPress for a list of our extensions. Alternatively, you can contact our support team through our dedicated helpdesk at: https://codewoogeek.freshdesk.com/support/home
Regarding your inquiry about customizing the subscription form, we recommend using our Custom CSS Add-on. With this add-on, you can easily customize the color and button size of the front-end subscription form according to your preferences.
Note: By considering WordPress norms and ours, we do not promote or enclose our add-on details here.
Thanks.