Thanks for bringing your concern to us, RobyneC.
There isn't an option for default VAT exclusive when creating invoices but not when creating checks. Though having this feature is good especially for those businesses who need a wider option for VAT setup.
While this is unavailable, I encourage you to visit this page for some product updates: Firm of the Future.
I'll leave you with the following article for more information about managing VAT in QBO: Set up and use VAT in QuickBooks OnlineCreate a new VAT code.
Visit these easy-to-access articles, webinars, and video tutorials that will help you in familiarizing the different tasks, features, and functions of QBO.
Of course, you're always welcome to visit us again if you need help while working with QuickBooks. It will be my pleasure. Stay safe and have a great day ahead!