Hey, anything is possible with HA ;).
That being said, it is important to understand how Home Assistant (HA) and this integration work to be able to answer your question:
The logic of this add-on is as follows:
- HA provides a framework in which this integration resides
- The Fujitsu integration is able to call the (open) HTTP endpoints of the air conditioning units(in HA = devices) to switch or read:
- different modes (in HA = entity ‘switch’)
- set the temperature (in HA = entity 'climate).
- By adding a aircon unit to the integration, you are able to execute all the commands that were discovered thus far.
What this means is that HA is able to contact the Aircon units.
Your question is if you can link Siri. In order to do this, you need first for HA to be able to read/set values to the Fujitsu units. Next, you need to expose information from HA to Homekit, the protocol/framework Apple uses to
Link to documentation: [HomeKit Bridge - Home Assistant](https://expose HA to Homekit).
A quick search tells me you are not alone in wanting this:
- [Expose Scripts in Homekit Bridge]
- [How to make HomeKit see more of your gadgets with Home Assistant - Ars Technica]
Best of luck!