Modification to a VOD Woocommerce

!! Read carefully please and DON'T bid automatically !! I have this french woocommerce site where people buy access to videos or pdf files. To be specific: they buy access to a secured page on which is embeded either a video or a pdf file. To do that, I use a plugin that is called "pay for post". This plugins allows to link a page to a woocommerce product. After their purchase, the customers have access to all their purchased content in the "my account section" under the "access your content" (mon compte / accéder à votre contenu) tab. On the home page is the list of all available content (that's the "shop"). When you hover the thumbnails or click on them you get the option to add the product to cart (button "ajouter au panier"). Which is a very standard woocommerce behavior. Now, if the customer has already purchased a content, when he clicks on "add to cart", a message is displayed saying "you have already bought this content, you cannot buy it twice" (in french : "Vous avez déjà acheté ce produit. Vous ne pouvez pas l'acheter une seconde fois."). To achieve that, I use a quite straightforward plugin that only allows, one-time buys, it's called "Woo wolly one time buy". Now.. What I want is when people have already bought a content, instead of the "add to cart" button, they see a "access to content"" ("Accéder au contenu") button redirecting them to the associated content page. If you have questions, please ask me. Thank you.