Exposing devices to Google assistant

Having bounced round the setup process for Google Assistant integration more times than I can count I am wondering if I have hit a bug in HA or I’m missing something.

Project in Google Cloud :heavy_check_mark:
Yaml entry in configuration.yaml :heavy_check_mark:
Exposed entities in HA :person_shrugging:
Entities available in Google Assistant/Home :x:

The “expose entity” seems to be missing any reference to Google assistant, even though the configuration entry exists and I can see some logs in the Google cloud console when a resync is forced. Should I see Google assistant as an option in the expose entities screen in HA or is that only a Nabu Casa thing?

Any ideas or input appreciated :cowboy_hat_face:

AFAIK those entries are there only when Google Home is set up though Nabu Casa Cloud.