Hi there, @jevansstaffcom.
Thanks for getting back to us and for providing additional details about your concern. Allow me to jump in for a moment and share some information about archiving expenses and invoices in QuickBooks Online (QBO).
Archiving past transactions on both Expenses and Invoices tabs is a great idea! I can see how this feature would be helpful for you and your business. While it isn't available yet as @AlcaeusF mentioned, I'm going to send feedback regarding this directly to our Product Development Team for consideration in future updates.
I also encourage you to submit feedback as well. QBO is constantly changing and evolving based largely on the suggestions and requests of users, like yourself. This will also help our Product Developers know how this option makes your QBO experience smoother.
This can be done directly through your account by clicking the Gear icon in the top right corner, then select Feedback or by going to the following link: QuickBooks Online Feature Requests.
That should answer your concern for today. Don't hesitate to post again here in the Community or leave a comment below if you have any follow-up questions. I'm always here to help. Take care and have a great rest of the week.