The Finder Info window should reflect the actual status of a ZFS pool.
1. Create a macOS friendly pool (case insensitive).
2. Activate the HFS mimic feature on this ZFS pool.
3. Select the pool in the Finder and hit Command-I to bring up the Info window.
Currently (ZFS 1.9.3.1) the Info window describes the pool as Mac OS Extended (case sensitive).
I suggest the mimic feature should reflect the actual case sensitivity of the pool in the Info window.