I know it is not the idea of Workspaces, but one of our use case.
I want to share a workspace. The receiver should not be able to even see (and of course work with) the given dimensions, metrics and segments. All options i see with the permission regulation finally generates not such an outcome.
You can manage the dimensions , metric, report suite access along with workspace permissions through a product profile in Experience cloud > Admin console. Users would be able to access workspace only for listed dimensions/metrics/report suites.
Here is an article on it: https://experiencecloud.adobe.com/resources/help/en_US/mcloud/admin_getting_started.html
You can also choose to curate your project and share it. This will provide option to allow access to specific dimensions/metrics/segments from your workspace. Here you'll find more details on it: https://marketing.adobe.com/resources/help/en_US/sc/appmeasurement/osx/context_data.html