Which Dungeon Magazine adventures can be used for Dark Sun with minimal changes? I’ll go first.
The Siege of Kratys Freehold Dungeon Magazine #33 (review).
This is a siege scenario. Swap out the orcs for gith, and the freehold for an oasis with a walled compound.
Dungeon Mag, #37. Mud Sorcerer’s Tomb.
I’ve mentioned elsewhere that I converted Beast of Burden (Dungeon Magazine 100) to Dark Sun.
The Pyramid of Jenkel, Dungeon Magazine #23. Swap out the Abhir (Knock off Marilith) for something else cunning - maybe an Elder Psurlon, or even a trapped Succubus with a few levels of Defiler for good measure. Swap out the trolls for belgoi (or even undead trolls), the ogrillons for gith (that old stand by), and the kamadans for displacer beasts (or leave them as is - there are 3.x stats out there for them including Dungeon #136). The idea of the corrupted village above underground ruins strikes me as very Athasian, in a Wicker Man sort of way.
Personally I kept the gate to the Tarterian Depths of Carceri in the game - if any of your players want to get to the Outer Plance then managing to make it but trapping them on Carceri is a great way of messing with them. 
Hmmmm… Or why not make Athasian ogrillons half-giant/gith hybrids? Alternatively, ogrillons can exist as is. Just because ogres and orcs do not exist doesn’t mean that the hardy hybrids did not survive.
That’s an interesting question when you think about it. During the Cleansing Wars, which Champion had ‘dibs’ on hybrid races? Did Albeorn have responsibility for slaughtering Half Elves? Did Kalak or Uyness deal with Ogrillons? I guess none of the hybrid races were big enough to form their own societies - Half Orcs and Half Elves are most numerous in default D&D but there aren’t kingdoms, cities or settlements purely inhabited by them.
I got to thinking about half giant half gith and decided that it’s unlikely. Gith are egg layers, which means that gith are probably incompatible with mammals. And before you say “half dragon” (in other settings), those creatures come about because dragons are capable of polymorphing.
That doesn’t mean that other gith hybrids aren’t possible. Gith might be able to breed with other egg layers, which opens interesting possibilities.
I didn’t quite realize this until you brought it up. I used very few Dungeon adventures in all the time I had ever run things.
I might guess that I would adapt Dungeon #96 magazine Pandemoniun in the Veins. It’s about gladiators and an arena.
Not dungeon magazine, but ‘Escape from Zanzer’s Dungeon’ is ripe for a conversion to Dark Sun.
Could also use Sligs, T’ulk, or Taregs depending on how you want to flavor it and whether they are near the mountains.