You can include a balance transfer request when you apply for a CommBank credit card online. There’s a section in the application that asks you if you want to transfer a balance. If you select "yes", you will be asked to enter details including the name of the financial institution you want to transfer a balance from, the card number of the accounts and the amount you want to transfer from each eligible account.
You can request a balance transfer from personal Australian credit cards or store cards, with a minimum transfer amount of $500. This request is subject to approval. Note that you won't be able to get a balance transfer on a CommBank Essentials or CommBank Neo card, as they do not offer this feature.