Currently in GCP compute engine instantiation of a supported VM and a Virtuoso standalone installation on it is the only deployment method available. We are currently working on GCP BYOL and PAGO Virtuoso Marketplace offers, as we already offer for AWS and Azure, which should be available soon.
By Bulk load do you specifically mean with the Virtuoso RDF Bulk Loader ? As with something like PyODBC you can make an ODBC connection to Virtuoso from python and then run the same commands as in sql to setup and run bulk load operations …