FYI: Google Pay drops Visa Checkout support before the service shuts down in 2020
In this regard, 9to5google reports Google Pay has already dropped Visa Checkout support or plans to do it very soon. Any information related to Visa Checkout has been removed from the “Supported accounts & services” section of Google Pay support page, which suggests support for the service might be going away soon (if not already).
Currently, PayPal is the only other online payment service supported by Google Pay, although Visa announced plans to replace Checkout with a more robust online payment solution based on EMC SRC.
Consumers will be able to continue to use Visa debit and credit cards with Google Pay, but they won't be able to connect the two services once support is dropped. Although Visa announced that it's migrating Checkout to a new online payment solution, it's yet unclear if Google Pay will add support for Visa's new solution.