I'd like to give some details about the payroll service in QuickBooks Online.
Just to clarify, the South African version of QuickBooks Online doesn't have a built-in payroll service.
If you're planning to use a version with a built-in payroll service (US, UK, Canadian, or Australian versions), we're unable to customise it for Zimbabwe and Botswana tax tables. Each payroll service in QuickBooks specifically caters to their own country.
However if you're using a third-party payroll plugin, you'll want to contact the developers or the app's support channels. They'll give the steps on how to customise your plugin for Zimbabwe and Botswana taxes.