QB is only allowed to use 1 currency in 1 transaction. You may open a virtual bank account at TW to deal with multi currency transactions and run the bank feeds.
QuicBooks Online support multi-currency, deepthi-gopineed.
This feature is available in our Essentials and Plus versions. You'll need to turn it on first and set it up.
Once done, you can add to the currencies you want to use. Please check these articles for more details:
Post again here if you need anything else. Wishing you all the best!