While a payment gateway might support a physical payment card reader (credit cards, debit cards, digital wallets, etc), at this time, Soapbox Engage does not provide an integration with any payment card readers. This is true for all of our apps, including the Donations, Events, and Shop apps.
For organizations needing in-person, point of sale (POS) payment card readers, we recommend contact your payment gateway for options that work best with your payment gateway.