Yes, you can use URL parameter in this case.

  1. For signup button, navigate to signup page directly. And for login page pass an extra URL parameter ?login=true.
  2. Now, in signup page, on page load action, you can check if URL parameter has login=true then hide the signup group and show the login group and hide the URL parameter by Go to page action so that after loading the page this extra parameter is not visible to the User.

Hope this helps!