Hi Frayedknots,

Thank you for getting back to us on this. 

I would suggest you to refer to this article from our online community on how to handle bank charges (you can treat the transaction charges in a similar way that bank charges work):

How to account for Bank Fees when matching transactions in Bank Feed

- https://quickbooks.intuit.com/learn-support/en-us/banking/how-to-account-for-bank-fees-when-matching...

In short, create an expense account for the transaction fee charges. When matching the transaction from banking, still match the $10 you invoice your customer, but as you only received $8, QBO is going to ask you if you want to resolve the difference. Select yes, and enter the fee amount as an expense. You do need to put the fee amount ($2) as a negative amount (-$2) in the resolve difference screen but if you click save and check back on the expense transaction created by resolving the difference, you can see the amount on the expense is positive. 

I have tried it in my test file and it worked for me. Please give it a try and see if it works for you as well. 

I would also suggest you to consult with your accounting professionals on this. 

Please let us know how you go.