Draconoid is a scrapped, forbidden, and unknown Bakugan that was supposed to be released in season 1 toylike of Bakugan, infact, it was supposed to be the main villain instead of Naga.
Dragonoid is very similar to Dragonoid, but has an extra set of wings that are sharp, and Draconoids appearance is scary and demon like.
Spinmaster accidentally posted on the Bakugan site on the Bakugan list section, showing a shadow version of Dragonoid, but it was called "NULL", and there was no description. Fan's thought it was the villain Bakugan and they came up with many names, until some person made a typo when describing the Bakugan as exactly like Dragonoid, the person called it "Draconoid" and it was spread on 4chan.
Nearly after, "Draconoid" disappeared off the Bakugan website, and it was forgotten and possibly scrapped, it is unknown if it would ever be released, but probably not due to Bakugan being discontinued in America.
Although Draconoid was never known or shown again, in the Japanese version of Mechtanium Surge episode 46, there is a deleted scene where Draconoid is mentioned by Genesis Dragonoid, where Genesis Dragonoid quotes: There was also a dark clone like you, but he was destroyed. Fans believe that it might have been Draconoid, or Fury.. Or even Dharak.
In the first volume of the Bakugan DVD, Drago talks to Naga after he is crossing to Earth, but there is a shadowy figure that can be seen with a good eye. This might have been Draconoid as well.