Will someone with a Belgian banking app still be able to scan a QR code created with the Bancontact Pay app?

Yes. You can still create QR codes in the same way as before with your Bancontact Pay app, and these codes can be scanned via the Bancontact Pay app or with one of the bank apps listed below.

The reverse is also true: Bancontact Pay app users can still scan QR codes created with the bank apps listed below.