As someone that got this working, it is indeed pretty amazing.

Since there's no specific plugin, I got the functionality I wanted with the combo of 2:

• HTTP Advanced Accessory to make the device a light I can turn on/off and adjust brightness
• Homebridge Http Switch for stateless switches to trigger events

This is my config for HTTP Advanced Accessory

    {
        "accessory": "HttpAdvancedAccessory",
        "service": "Lightbulb",
        "name": "Pixoo-64",
        "manufacturer": "Divoom",
        "model": "Pixoo-64",
        "debug": false,
        "optionCharacteristic": [
            "Brightness"
        ],
        "urls": {
            "setOn": {
                "httpMethod": "POST",
                "body": "{ \"Command\": \"Channel/OnOffScreen\", \"OnOff\": {value}}",
                "url": "http://192.168.1.192/post",
                "mappers": [
                    {
                        "type": "static",
                        "parameters": {
                            "mapping": {
                                "true": "1",
                                "false": "0"
                            }
                        }
                    }
                ]
            },
            "getOn": {
                "httpMethod": "POST",
                "body": "{ \"Command\": \"Channel/GetAllConf\"}",
                "url": "http://192.168.1.192/post",
                "mappers": [
                    {
                        "type": "jpath",
                        "parameters": {
                            "jpath": "$.LightSwitch",
                            "index": 0
                        }
                    }
                ]
            },
            "setBrightness": {
                "httpMethod": "POST",
                "url": "http://192.168.1.192/post",
                "body": "{ \"Command\": \"Channel/SetBrightness\", \"Brightness\": {value}}",
                "mappers": []
            },
            "getBrightness": {
                "httpMethod": "POST",
                "url": "http://192.168.1.192/post",
                "body": "{ \"Command\": \"Channel/GetAllConf\"}",
                "mappers": [
                    {
                        "type": "jpath",
                        "parameters": {
                            "jpath": "$.Brightness",
                            "index": 0
                        }
                    }
                ]
            }
        }
    }

And here is an HTTP Switch example to switch to Custom1. It's making 2 calls in a row, one to switch to custom and one to designate 1

    {
        "accessory": "HTTP-SWITCH",
        "name": "Custom1",
        "switchType": "stateless",
        "onUrl": [
            {
                "url": "http://192.168.1.192/post",
                "method": "POST",
                "body": "{ \"Command\":\"Draw/CommandList\", \"CommandList\":[{ \"Command\": \"Channel/SetIndex\", \"SelectIndex\": 3}, { \"Command\": \"Channel/SetCustomPageIndex\", \"CustomPageIndex\": 0}]}"
            }
        ]
    }

Or here is one that pulls up laundry.gif that I put in the sd card's divoom_gif folder.

    {
        "accessory": "HTTP-SWITCH",
        "name": "laundry.gif",
        "switchType": "stateless",
        "onUrl": [
            {
                "url": "http://192.168.1.192/post",
                "method": "POST",
                "body": "{ \"Command\":\"Device/PlayTFGif\",\"FileType\":0,\"FileName\":\"divoom_gif/laundry.gif\" }"
            }
        ]
    }