I don't know about your bank/countries, but all of the banking apps in my country I've seen have 1. a "share account details" button that lets you easily paste your IBAN and other details in text form and 2. a "transaction receipt" button that saves a .pdf with the relevant details, that can be sent to the other part (although I agree with the other comment, this .pdf just like a screenshot can be easily spoofed)