See DSP-11303, DSE Graph for version 5.0.4 will be accepting a new key in the custom payload that will allow drivers to choose the subprotocol format for returning JSON results.
There are 2 formats available so far, GraphSON 1 and GraphSON 2.0.
The payload key is "graph-results". The current possible values are "graphson-1.0" and "graphson-2.0".
We need first to discuss whether we want to expose an API to users to be able to use this new option, and/or discuss whether we should decide to drop GraphSON1 and always choose GraphSON2 results format from now on.