Provided that both databases support the model you have written in the Graph.Build studio, this is as simple as running two Graph Writers, one for each database. You could take this further though and make changes to the model in the tool, for example reworking it as a labelled property graph rather than an RDF graph, then run both versions of the solution in parallel to test the two conceptual models against each other with different graph vendors. The choice is yours because the capability to do testing quickly is within the platform.