So - if the second form uses input parameters, those can be passed in via the URL. But you'd need code in the second form to use those input parameters - are these browser forms? If so, you could host form 2 in a web part, then pass in a query param in the URL, and use form load rules in the second form to get data from the first form. For example, your URL in the workflow could include the form name for the first form, and in your second form, that data could be used to query for the first form, then use rules to set field values in the second form....