Hello, @Bujet.

I hope you're having a successful business week. Currently, the option to import invoices with sales tax into QuickBooks Online is not available. This is why you keep getting the error message "Import invoices isn't quite ready to support sales taxes." However, you can check out our third-party app options to see if they offer an app that supports importing invoices with sales tax. 

Feel free to comment below if you have any other questions. Enjoy the rest of your week!