For my Mastercard credit cards from HDFC and RBL, via BharatQR, it says "Merchant name MUMBAI IND" but for my Visa CCs, it says "Merchant name Visa Direct, IND".
Payments via credit cards are considered online transactions in GPay. I confirmed this via my IDFC FIRST Bank Classic credit card whose statement clearly shows monthly offline (3X RPs) and online spends (6X). Wherever and whichever month I've paid using this card via GPay, every statement says 0 RPs for offline but I see a ton of RPs accumulated on online.
This makes sense that they would be treated as online transactions because the card as you know is tokenized. We enter the actual card numbers, expiry and CVV just like an online transaction when storing the card, only instead of storing it as plaintext, it is encrypted. And of course, we've to enter the OTP as well just like for any online transaction.
So that answers the question about SBI Cashback card as well. You will get 5% cashback if scanning and paying via BharatQR.
Oh and UPI QR code scan and pay transactions via RuPay CC are also online transactions but of course, banks have a reward structure that is different for UPI RuPay CC transactions. But the statement again shows 0 RPs for offline for IDFC FIRST Digital RuPay CC.