Let me help share some insights about exporting transaction from QuickBooks Online.
At this time, being able to export month's transactions from QBO wherein each row exported has all the data fields filled isn't available. However, you can export the transactions and create a pivot table from there.
Additionally, you can check out for some third party application that can extract the format that you need. You can do this by visiting our App page on your QuickBooks Online account.
Log in to your QuickBooks Online account.
From the left pane, click on Apps.
Search for apps in the search box.
QuickBooks displays the list of applications available that matches the description you entered. Once you find the right app, click on it to open. You can also visit this link for a better view: https://apps.intuit.com/.
From there, you can find different apps that are compatible and designed to work with QuickBooks depending on your business needs.
Also, you make check out these articles about exporting reports in QuickBooks Online for your future reference: