A: The information collected in the Residency, Personal data, and Contact details pages. When it comes to the Tax Forms info page - you can transfer the questions and fields related to Form W-4 only. The rest of fields can be imported by an admin via a demographic import CSV in Imports -> New Imports, or can be left to the end user to complete.
Apart from this, you can choose to transfer over any e-signed/uploaded tax forms with a valid expiration date, i.e. - Form W-8BEN, Form W-9, Form W-4, etc.
You also have the option of transferring over any uploaded documents, not including tax forms. For example - a copy of passport, visa, I-94, etc.