The ability to edit your bills payment voucher title from Remittance Advice to Payment Voucher in QuickBooks Online is unavailable. I can see how the functionality to edit your voucher tittle would be beneficial to your business.
That said, I'd recommend sending a feature request directly to our Product Development team. This helps us improve your experience and the features of the program.
Here's how:
Go to the Gear menu and then select Feedback.
Type in your feature request in the description box.