It's nice to see you again, @edenwillow.
In QuickBooks Online Advanced, you can import multiple invoices at once. There is also other information that will be imported, these are:
- Can import a maximum of 100 invoices at a time and 1,000 row limit per spreadsheet.
- Can import invoices with single or multiple line items.
- Can also import a large volume of customers and vendors or products and services.
However, at this time, the option to import with classes isn't an option. As a workaround, you'll need manually assign classes when imported or you may wish to consider checking third party applications. Just visit the QuickBooks App Center through this link https://apps.intuit.com/.
Additionally, to learn more about importing invoices, you can check out this reference: Import multiple invoices at once.
You’re always welcome to visit us again if you have other questions concerning QuickBooks, I’d be happy to further assist you. Take care.