How to identify Edge Client and redirect to different hostname?

There is a "Client Type" action in the VPE. My suggestion would be to add in the VPE for the webtop policy a check for the edge client and if found then use the redirect ending type and redirect to the SSLVPN VS. You could also add a client type to the SSLVPN VS and if using the browser redirect to the webtop VS.

-Seth