I guess the short answer is that there is not a  way to tell QBO to leave certain transactions uncharacterized. 

I do understand how to recharacterize transactions before I confirm them. It makes the workflow harder because I have to be logged into my bank account to see what each transaction is for and by the time I scan or download  and attach supporting documents my bank has signed me out and i have to sign in again to process the next one. If they weren't characterized then I could characterize them all with the bank account open and then go back and add supporting documents after.