Stardog is an RDF database with strong support for SPARQL and OWL that can be extended to provide labelled property graph capabilities (thanks to support for RDF*) with support for Apache Tinkerpop and Gremlin.
Stardog’s emphasis is on building and supporting enterprise knowledge graphs, where you want to be able to view information and relationships – and explore these – across multiple, heterogeneous data sources. To support this, the company also provides Stardog Studio, which it describes as a Knowledge Graph IDE. Although it is graphical it is intended for use by developers and administrators rather than end users. It includes contextually aware auto-completion and hints for editing graph queries, mappings, rules, and graph data models.