It's possible to import bank transactions easily from the Bank screen, by adding a "Credit card" account, and uploading your transactions from the past.
1- export your previous bank transactions from your bank app
Export all your banking data from your bank account, in .PDF or .CSV format (you would need to then save the .CSV in an PDF or JPEG format to be imported into the bank screen).
2- Create a new "Credit card" account
First, connect to the Bank screen on Accountable web.
From this screen, click +Add > credit card
3- Import your bank transactions
From the next screen, you can update, add, or delete a transaction
After you confirm, transactions will be visible like a normal bank account