A second approach may be to automatically load all of the staff details via a CSV file, and then to load the client groups and users manually as you onboard them.
Before creating the staff CSV upload file, you need to create all the staff groups that these staff will belong to. This too can be loaded via a CSV file, but there is typically only one or two groups which can just as easily be completed manually. Make sure you assign a unique identifier value to these groups as this is required to import members into the group via the CSV.
Once you have your groups loaded, populate the CSV template with your staff details. To access the template, as a system or user administrator, navigate to the Staff option on the Organisation Settings side menu.
Select Upload Staff and you will see in the text description links to a blank template and a populated sample.
When uploading your staff, you will see on-screen all of the records and their status ahead of the import process. Once you are happy that all of your records are loaded correctly, you can then press the Submit button to execute the load.
Make sure you DO NOT select the option of "Do not send the invitation email" as this will prevent the invite emails from automatically being generated.
Once all staff have accepted their invites, you can then set up the contact groups for your client users, add their staff members, and then invite your client users.