We have plans for developing and releasing a .NET Core Identity provider as part of the Couchbase.Extensions for .NET Core project on couchbaselabs. I don’t have a timeframe, but I would imagine it would be sometime later this spring. We are currently working on next-gen Couchbase features in the SDK, but will jump back on these projects soon.
As for support, they are both currently community driven projects, however based upon interest, they could become officially supported in the future. If your interested in using them, feel free to provide feedback, report bugs or request a feature using the Github issues tab on each project. Also, both projects are open-source and we welcome any contributions big or small!