This is a small straightforward plugin having 2 modes to conditional redirect to an external URL.
Plugin action that can be used in Workflow when a certain event happens. Ex.: Redirect to an external URL if current URL contains a certain substring.
Element "Redirect". Add it to your page and provide "Condition" and "URL" fields. Once "Condition" becomes true, you will be redirected to provided URL.
Check the demo for a better understanding.