Payrolls are not generated with invoices, so the best way to register them is with journal entries. For this, the best option (always validate with the client) is to do it in the following way:

1. Create a journal for miscellaneous payslips.

2. Create the contact for each of the employees (these must appear in the contacts app, not only in the employees app, so that they can be selected in the accounting lines).

3. Create the corresponding journal entries and enter the name of the contact in the company field.

4. Create one journal entry per employee (image 1) or create one journal entry per month and enter all employees (image 2).

1):

2):