MQTT Statestream variable in publish topic

Configuration
1

Hello,

I’m trying to send more HA clients states to a central MQTT server and log them. All of the HA instances has different user for the MQTT broker, and I was wondering if somehow i can use that username variable to set the publish topic, something like this:

mqtt_statestream:
  base_topic: {{ mqtt.username }}/states
  publish_attributes: false
  publish_timestamps: false

Many thanks

Tibor