How can I see expenses that have not been matched in banking?

Hello, @Darby5

You can check the transactions from the For Review tab. Transactions under that feed aren't yet categorised or matched. 

Here's how:

1. Go to the Banking menu and choose the blue tile for the account you want to review.
2. Select the For Review tab to start your review.

Check this article for more information: Categorise and match online bank transactions in QuickBooks Online. Also, the following article on how how to create, edit, and delete expenses: Enter, edit, or delete expenses in QuickBooks Online. 

Let me know if there's anything that you need. I'm always here to help. Have a wonderful day!