Web Form with Dynamic Signatures

I want to create a Web Form where the signers are not known in advance.

The first user would open the Web Form, enter their name and email address, and sign the document. They would also enter their manager's email address into a form field.

Once the user has signed, I would like Adobe Sign to automatically send the document to the manager's email address entered in the form so the manager can review and sign it.

Is this possible using Adobe Sign Web Forms and Workflow Designer, or would I need to build a custom solution using the Adobe Sign API?