I'm glad that you reached out to us, kolpasky. 

QuickBooks Online sends your sales forms using the email “QuickBooks@notification.intuit.com.” It is set up this way so that you’re updated on the status of the sent invoices. The program will tell you when the sales transaction form was viewed, sent, or paid. As of the moment, the option to change the sent from is unavailable  in QBO. I can send feedback to our engineers about your suggestion. This way, it might be given a chance to be added when roll out product updates.

As we assess this opportunity, I encourage you to visit our QuickBooks Online Blog to stay current with our news and updates.

I've included an article that will help you personalize your sales forms in QuickBooks Online: Customize your invoices, estimates, and sales receipts.

If you have any other concerns or questions, please tag me below and I'll get back to help as soon as I can. Take care!