So I have a plugin that's a little complicated to set-up but it should work for your needs. It basically is a REST API proxy using MQTT subscriptions. Install the MQTT plugin, then install the OctoPrint-MQTTSubscribe plugin using the url
https://github.com/jneilliii/OctoPrint-MQTTSubscribe/archive/master.zip in Plugin Manager.
Once both plugins are installed, go into MQTT settings and configure the connection to your MQTT server. Then in the MQTT Subscribe settings configure the index, topic, type and command to base your subscription on. These should match the REST API commands, so in your case you would set it up like the highlighted part in the image below, which is the equivalent of the Example Disconnect Request over here. The API KEY can be obtained from your user settings, from the flyout menu on your name in the top right of OctoPrint and is required for the REST API functionality to work.
Then in Home Automation use the MQTT Topic
/octoprint/plugins/mqttsubscribe/connection/1 and data to submit should match the REST API payload, ie
The REST API response status code and text will be returned to the respective mqtt topic/index so you can act on the result of the command that was sent.
Status code gets published to
Response text gets publishd to
In theory any of the API commands could be used, as long as the information matches between the plugin settings and the information necessary to submit to REST API. I'm sure there is something that will have to be tweaked here and there. I think I might remove the match required between REST API payload and the plugin's command settings and just use the topic and index. Would probably be good to add an automatic index generator and distinct index validation.
Please submit issues to the plugin's issue tracker here.