That refers to features that are specific to the plug. On/off and energy meter functions are generic across the family of devices, so are also supported on the HS100.
(Context: I wrote the initial support for bulbs in this module, the plug support already existed)
The way the hole text is written, and even your response, makes still not clear for somebody not involved in the project what actually works, so please take that as a hint for somehow presenting the information that you have so that the others can easily understand it. I know it's a small thing directed to maybe a small number of potential users, but maybe you still lose someone valuable due to the confusion.
By just reading what's there it gives the impression that, surprisingly, that project has less basic functionality than the bash script.
https://github.com/GadgetReactor/pyHS100