Welcome to the Community. Allow me to share some information about pulling up an expense report in QuickBooks Online.
Currently, pulling up a report that shows the total sales less of a product expense is unavailable in QuickBooks Online. However, you can pull up the Expense by Vendor Summary Report. This shows all the expense transactions that were entered in QuickBooks.
To do that:
Click on Reports on the pane.
On the search box, type in Expense by Vendor Summary.
Enter the date that you wish to pull up.
Click on Customize at the top.
Click on the Rows and Columns drop-down arrow.
Under Columns select on TotalOnly.
Click on Filters.
Put a check-mark on the Customers box.
Also, I can see how this feature would be helpful for you and your business. I encourage you to submit feedback, which is sent to the Product Development Team for review when determining features to be added in updates. You can do this from within QuickBooks Online by selecting the Gear icon and clicking Feedback or by going to the following link: QuickBooks Online Feature Requests.
Please let me know if I can be of additional assistance. I hope you have a wonderful week ahead.