Thanks for joining this thread, @swdv-sg.

In QuickBooks Online you can  track transactions using more than 1 class categories. For example, you can assign an item to one or more classes when creating a transaction. Let me walk you through the steps:

1. Log in to your QuickBooks Online account. 
2. Click the +New button and select the type of transaction you want to record.
3. Enter the necessary info.
4. In the Item details section, add a 3 line items for a single item and assign it to different classes.

To know more about the class tracking feature in QBO, you may visit this article: Class tracking in QuickBooks Online. 

Then, you can run several class reports to track transactions by class. For the detailed steps here is an awesome link that you can open: Run reports by class.

Feel free to leave a reply if you have more questions about class tracking in QBO. I'll be here to answer them for you. Stay safe.