Hello there, @craneuser.
Thank you for posting in the Community. I can provide clarification on QuickBooks Online (QBO) supporting Accounts Receivable (A/R) and Accounts Payable (A/P) accounts.
QuickBooks Online allows you to have multiple Accounts Receivable, however, the invoice created will use the default accounts receivable. But, I have a workaround that you might want to consider. You can create a Journal Entry to move the amounts from the default A/R account to the other A/R account.
Just a heads up, it would be best to reach out to your accountant so they can guide you further.
You can also use this reference for the detailed steps in creating a journal entry: Journal Entry.
I'm just around the corner if you still need my help.