Hi,
thanks for reaching out. This is one of the reasons for this warning in the plugin description: Donation Platform for WooCommerce turns WooCommerce into a donation system, parallel use as a normal store is not recommended, as some wording has been changed.
You can change the text back using the following snippet:add_filter('woocommerce_product_add_to_cart_text', function() {return "Add to Cart";}, 15 );
Best
Jonas