Is there a way to consume MQTT JSON payload in Ignition without cirrus link driver?

Yes. That is the idea behind my ActiveMQ project. [project] ActiveMQ Integration - #7 by dmdrendall

http://recordit.co/1IQLCetu9s

http://recordit.co/PFDz9ObMsR

Although, there is much to be said for SparkplugB support in CirrusLink modules.