Google already announced the end of Google Trusted Stores program. It is being replaced by Google Customer Reviews.
Google Customer Reviews Integration module for XC4 is now available here
https://www.cflsystems.com/google-customer-reviews-integration-for-x-cart-classic.html
The module is released for XC 4 versions 4.6.x and 4.7.x. If you need it for earlier versions please let us know.