The current limitation: "Printing using feature report templates does not work with ArcGIS Enterprise deployments that aren't public facing. Attempting to do so will present a getaddrinfo ENOTFOUND error." Found here.
However, the sensitivity of the data I work with can only stay in Portal and the end result of a Feature Report is preferred over the non-formatted print view when clicking on an individual report within Data. Would you enable Feature Reports in ArcGIS Enterprise? Also since Feature Reports is not an option in Portal why is it enabled and why is it even there to begin with? This creates confusion for the user and requires time wasted in digging around for a solution when there isn't one.