Ooh. Okay, so back in the summer of 2015 prepping to run a grand campaign of Mummy's Mask, I systematically went through every reference to Osirion in all of Paizo's works, built a detailed map grid of the nation and everything with a spreadsheet listing cut and paste bits of what was at every location in the nation, along with adventure and book references so I could find them again. This was well after the various Osirion support books came out for Mummy's Mask, so my guess is that it's relatively complete. So, searching it for "dragon":
1. On the edge of Northern Qadira/Southern Osirion is a place called the Gembasket with a blurb in Dark Markets (page 7): "Rumors also persist that a red dragon has claimed the Gembasket as its territory; while no reliable sightings of the creature exist, badly mauled and burned corpses occasionally turn up on the steep mountain slopes"
2. In the middle of the Glazen sheets is an adult blue dragon named Susurex who lives in a glass fortress of mysterious origin. He calls himself the Crystal King (detailed in the Osirion Campaign Setting book)
3. The volcano called Asuulek's Mouth is named after the ancient red dragon that makes the volcano its home. There's quite a bit of detail about him and his activities in the Osirion Campaign Setting book.
4. In Mummy's Mask #4 there's a fun encounter with a young blue dragon who has built an elaborate stone garden (The Garden of Symmetry) in the middle of the desert. He's got some fun OCD like character to him.
5. Also in Mummy's Mask #4 there's a brief plot hook of a Desert Giant who's been searching for his army for thousands of years and if the PCs help him, he helps them when ambushed by an adult blue dragon.
That's all I've got. Osirion isn't a very dragony place and the ones that are there seem to mostly be old blues and a really old red. Probably something there for you to work with though.
