Had a similar experience with azure cosmos graph API. The API is half baked. Doesn't support all gremlin operations. Even supported operations give non standard output. Switched to aws Neptune immediately when they launched
Doesn't surprise me. Cosmos was too good too be true :
- Serverless - Infinite Scalability - Mongo API or Gremlin API or SQL API
It's obvious that it can't hold up to all it's promises.