Substreams with order and dispatcher, instead of ConsistentHashingPool with ask+timeout with blocking processing

SubstreamsWithOrder.java

//without backpressure:
ActorRef myActor = system.actorOf(
				new akka.routing.ConsistentHashingPool(maxParallelism)
				.withHashMapper(hashMapper)
				.props(MyActor.props(blLogic).withDispatcher("my-dispatcher"))
				, "my-ordered-processor-pool");
		
final Timeout timeout = Timeout.apply(1000L, TimeUnit.MILLISECONDS);
		
Flow.of(Event.class)
.mapAsyncUnordered(maxParallelism, (Event e) -> ask(myActor, e, timeout));

//First try
Flow.of(Event.class)
.groupBy(maxParallelism, e -> Math.abs((long)hashMapper.hashKey(e)) % maxParallelism)
.map(e -> bLogic(e))
.mergeSubstreams()
.withAttributes(ActorAttributes.dispatcher("my-dispatcher"))
.async();

//define async and dispatcher on substream: Both parallelism and backpressure
Flow.of(Event.class)
.groupBy(maxParallelism, e -> Math.abs((long)hashMapper.hashKey(e)) % maxParallelism)
.map(e -> bLogic(e))
.withAttributes(ActorAttributes.dispatcher("my-dispatcher"))
.async()
.mergeSubstreams();