Below are some of the screenshots from Alexa.
There were other Daikin Skills but this is the specific one for Mobile Controller app that is used for Daikin WIFI enabled aircons sold in Singapore
You can adjust the set temperature and also view the current room temperature but you can only switch between Cool and Auto mode, no Fan or Dry mode which is supported by the aircon. It is also not supported by voice so it does not understand those modes either.
Google Assistant however have the options for all the modes supported by the aircon.
Will update with more details soon.