Maybe this will help you (ignore the Docker parts):
Otherwise just take a full backup, stop the Z-WaveJS addon, start the Z-WaveJS2MQTT addon, set it up to allow Websocket connection and use the correct USB path, wait for interviewing to complete (in case of battery powered devices you might want to wake them manually to speed up this process) and then reconfigure the Z-WaveJS integration within HA to point to the new addon. If the versions match up I don’t think (I know, assumptions) there should be any change in entities.