I understand that you want to minimize any inconvenience for your client, especially when it comes to handling transactions, Hanzala.
Since QuickBooks Online (QBO) doesn’t allow the currency for connected bank accounts to be edited, the only solution is to remove the existing account and create a new one with the correct currency.
To make this easier for your client, you can assist them by removing all the transactions from the account so they can just go ahead and delete it. This way, you can make the process as smooth as possible.
If you have any further questions, feel free to revisit this thread.