core/homeassistant/components/elgato/icons.json

{
  "entity": {
    "switch": {
      "bypass": {
        "default": "mdi:battery-off-outline"
      },
      "energy_saving": {
        "default": "mdi:leaf"
      }
    }
  },
  "services": {
    "identify": {
      "service": "mdi:crosshairs-question"
    }
  }
}