EngineMC (or sos!enginemc for short) is a port of the [StarOpenSource Engine](https://git.staropensource.de/StarOpenSource/Engine) to Minecraft and it's various plugin and mod loaders.
This means that events have to be registered manually. You can do that by calling [`EventHelper#registerEvent`](https://jd.engine.staropensource.de/v1-alpha6/base/de/staropensource/engine/base/implementable/helper/EventHelper.html#registerEvent(java.lang.Class,de.staropensource.engine.base.implementable.EventListenerCode,de.staropensource.engine.base.type.EventPriority))).
If you want to use a specific subsystem, either find or make a plugin/mod porting that subsystem to Minecraft (best option), or shade and include the subsystem in your final JAR and hope nothing breaks. Only do that if you have no other choice or the subsystem is specific to your plugin or modification.