I’d like to also mention Shinryu appears in Bravely Default as an optional boss you have to beat to access the Vampire Castle dungeon. It’s not particularly difficult and actually one of the easier of the 6 dragons you must beat to get to the castle but hey it’s worth mentioning it appeared
I did find that in my research, but I didn't think it was worth a mention because it wasn't really THE Shinryu, it looks different and has none of its signature attacks or behaviors.
I find it a bit odd but fitting that the arguably big bad of the franchise has such few actual recurring appearances unlike it's rival Omega, which could be chalked up to its demise in NT. I have no doubt in my mind though considering that SoP is already building upon the prequel elements of F1's world from Dissidia that the collaborator is indeed Shinryu but I don't think it'll play a role as a boss. As for the primal version from XIV, it is implied by both CId and Omega in the Omega raid series that it's creation was inspired by Midgardsormr, who was the dragon Omega was chasing in XIV's backstory. I do think there was a missed opportunity to, instead of having Bahamut being randomly evil in some titles, have Shinryu be the evil counterpart to Bahamut considering unlike Omega, Shinryu has multiple counterparts that aren't connected to the main version.
