Hi Pryor1, 

Thank you for reaching out on this. 

I did some research and tested in my test file. Unfortunately said function is not available in QuickBooks Online although QBO would remember the account select from the last entered transaction and default that for the next transactions. 

I would like to encourage you submitting an in-product for said feature as an enhancement request. Here is how:

How do I submit feedback?
https://community.intuit.com/articles/1164890-how-do-i-submit-feedback