At the moment, there's no option to change the default A/R account in QBO. All invoices are automatically tracked and posted under this account.
I invite you to share this suggestions by clicking the Gear icon and then select Feedback under your name.
I'll also share this feedback with our product engineers so they can take a look at this. For now, I recommend checking the QuickBooks Blog to get updated with the newly released features.
Lastly, you might to check this article on how to group Accounts Receivable or Accounts Payable account types.
Just drop a reply if you have other concerns. We'll be around.