List<Order> list = Ebean.find(Order.class)
            .fetch("details", new FetchConfig().query())
            .order().asc("id")
            .order().desc("details.id")
            .findList();

So in the example above, there is a query join on "details" ... and this means the order().desc("details.id") needs to be removed from the main query and onto the secondary query (+query join).

This is also the same with filterMany.

List<Customer> list3 = Ebean.find(Customer.class)
            .fetch("orders")
            .filterMany("orders").eq("status", Order.Status.NEW)
            .order().desc("orders.id")
            .findList();

The filterMany uses a query join ... and so the above .order().desc("orders.id") is removed from the main query and put onto the filterMany query.