Feywild/Good Kingdom as "Djinnistan"
by Marc SaindonRather than rely on Elemental Planes, perhaps the various Djinn cultures can share the Demiplane of the Good Kingdom, with the Seelie-Unseelie struggle re-purposed by a Peri versus Div struggle.
Various desert oasis or mirages can serve as gateways into this Realm. These natural portals open randomly, so even with the help the stars the navigate, one oasis can be lost forever.
The Shadowfell counterpart would be something like a mix of the Egyptian Underworld (Nithian bygones) and an endless sandstorm at night. The storm occasionally pops into Mystara, and sometimes eats up entire settlements.
Notes:
Paristan
Mount Qaf
Div (mythology)
(Image from: https://www.deviantart.com/kgiasa/art/Desert-oasis-835034265)