All solutions I find about get addon state need create a REST sensor and token… I think the addon status sensor should come as standard, just like the available update one.
This would allow automation based on the state of the addon. For example, if z2m hasn’t initialized properly, post a warning, or if MariaDB hasn’t initialized manually start it and restart HA.
The supervisor integration adds cpu, memory, running and version sensors for each addon.
My bad. The sensors are disabled and I did not see they.
It is solved 
How can I activate the sensors? I can’t find them either
All sensors are disabled by default and the Integration page doesn’t mention how to enable this.
Can you share how these can be activated?
Ok, found it myself. Was looking at devices but you need to go to entities of the integration and enable them there. Which makes somehow sense as you might only want to enable a few of them…