This plugin based on the https://plugins.gradle.org/plugin/aspectj.gradle plugin and will be updated to work with Gradle 5/6, because the existing plugin seems to be no longer maintained and failed to use with Gradle 5/6 due to a deprecated function in the new API.
Here is the URL to the corresponding entry in the Gradle Plugin Portal: https://plugins.gradle.org/plugin/aspectj.AspectjGradlePlugin
Thanks to lambovg who initially provide a working Fix of this plugin..
More information and examples coming soon...