I have been using Katalon for about 2 years and have always used this Project settings> Email for my regression test execution. Recent versions is not supporting emails or is it only for paid subscribers? Have checked all your forums and documents available so far. None of the suggested options are working for my outlook or gmail or yahoo in 7.2.1version as of Feb 2020.
I just activated the latest version of Katalon Studio with a free account and I can see the email settings. Please provide a screenshot.