The woocommerce files related to the presentation of contents (templates) are in the
/ wp-content / plugins / woocommerce / templates /
In this folder you can see the base templates (among others):
archive-product.php - displays a list of products
single-product.php - details of a product
This single-product file will fetch the data from the / single-product folder ... it is in this folder that you can make changes to the product page ... still in this folder you can see the sub add-to-cart where you have the templates for the button.
How much to change the behavior of the button I do not know how it will be, but it is possible!
Another important thing , do not modify the files here, copy them to your theme folder so that it looks like this: ... / o_your_template / woocommerce / templates /. .. and then modify those files in your theme! If you modify them in the plugin folder you will run out of these modifications when updating woocommerce!