Yes john,
If it is a reply that you're receiving to an email that you sent via Lindy, you can just set the action (whatever you want to perform) to "After reply received" of a send email action.
If it is a completely unrelated outreach email that is a response to an email that was not sent by Lindy, then you need to use the email received trigger and set up some sort of filters on it (either the subject or sender or body contains) so that it's not triggering after every email received and is not too expensive.