While it would be interesting (but also very disappointing for me, because I prefer dragons over demons) if the Au Ra turned out to be some sort of Voidsent related race, it's highly unlikely. While there are some minor similarities between the horn styles you offer, there are also a lot of other Voidsent in the game that don't have horns at all, it should also be noted that the only ones that have horns that come to mind, also don't have tails, and the ones that have tails do not resemble the tails that the Au Ra have in the least.
I also recall at a few points in the story (I believe the story leading up to Haukke Manor, as well as during the Black Mage quest) that it is said that Voidsent cannot materialize outside of the Void without a host or an anchor, one could assume that the Voidsent aren't even capable of procreation as they are merely an extension of the Void.
My theory is this, the Au Ra are a race of people who have a similar appearance to reptiles or dragons. They are not born from Dragons anymore than Miqo'te are born from cats, they are merely another race. They have no ties to Eorzea, because most races didn't come from Eorzea to begin with and it's not that hard to believe that there are races we haven't seen yet that live on the other continents.
In short, my theory is that we will get entirely new lore related to the Au Ra, they are not the children of demons or shiva or dragons, they are just a new race that fits the dragon/ishgard theme.
I also recall at a few points in the story (I believe the story leading up to Haukke Manor, as well as during the Black Mage quest) that it is said that Voidsent cannot materialize outside of the Void without a host or an anchor, one could assume that the Voidsent aren't even capable of procreation as they are merely an extension of the Void.
My theory is this, the Au Ra are a race of people who have a similar appearance to reptiles or dragons. They are not born from Dragons anymore than Miqo'te are born from cats, they are merely another race. They have no ties to Eorzea, because most races didn't come from Eorzea to begin with and it's not that hard to believe that there are races we haven't seen yet that live on the other continents.
In short, my theory is that we will get entirely new lore related to the Au Ra, they are not the children of demons or shiva or dragons, they are just a new race that fits the dragon/ishgard theme.