Publish an MQTT payload within an automation to a remote MQTT broker without bridging

I would like to publish a payload (State of charge of my electric car) to a remote MQTT broker on my wallbox (openWB) without the need of creating a MQTT bridge on the HA.

I would like to fire a command like this in the automation:
mosquitto_pub -h -t openWB/set/vehicle/1/get/soc -q 1 -m “{{ states(‘sensor.plate_e_state_of_charge’) }}”

Is this possible?