Hi there, @kfranklin1.
You might be using class tracking when running the Sales by Product/ Service Summary Report. Generally, any expense account is not available in this reports since this only tracks sales. If you're not using class tracking, I'd like to ask for some screenshot to help you further..
In addition, some data won't match after downgrading because of the availability of the feature in every the QuickBooks Online (QBO) version. QuickBooks Essentials doesn't have class tracking which may also be the cause that you're not able to get those specific data in your reports.
I've attached these reference pages to see the updated features available and changes after downgrading the plan:
Please feel free to tag my name in the comment section below if you have other questions or concerns with QuickBooks. I'm here to back you up. Take care.