You'll be glad to know that you can download free customizable and printable invoice templates from QuickBooks, jameslarkin.
Our options include Word invoice templates, Excel invoice templates, Google invoice templates, and PDF invoice templates. You can select a template for your business.
Simply go to this link, Blank invoice templates, click the type of business invoice template, then click Download free. Your self-employed staff can then use this template moving forward.
Here's a sample screenshot for your visual guide.

You can also click Chat live now if you have more questions about the free invoice template.

Additionally, please know that the invoice template in QuickBooks Self-Employed is different from other QuickBooks account. You can browse this link if you need to create one: Learn how to add products and services to an invoice and send it to your customers.
Keep me posted if you have updates about your invoice template concern. Simply leave a comment below, and I'll get back to you.