The apache-apex documentation states that the order of events in processors is preserved (based on how they are emitted), but does that mean that there is no event-time concept that allows out-of-order processing of events?
Moreover, can events be re-prioritized based on their contents, e.g. when they contain special phrases (e.g. AUTH in a security context). NiFi allows this, which is useful in situations with limited bandwidth.
Apache Apex doesn't support event time processing natively. Event time can be handled on the operator level with time bucketing (which allows for late / out of order arrival).
It is, however, a roadmap item. You can express your support for it with the community so that it will take a higher priority.
Native support for event-time windowing https://issues.apache.org/jira/browse/APEXCORE-414
Overall roadmap http://apex.incubator.apache.org/roadmap.html
For the second scenario, you can create a separate path in the DAG based on the content.