Yes! I always wanted to adventure in the Baklunish lands, but the closest I got back in the day was the Baklunish kingdom of Ket. The DM then lured our party into the Bramblewood Forest and eventually up in to the Barrier Peaks, where we got wiped! I wanted to take parties there when DMing AD&D1e, but the players always wanted to go east or start out east in the Great Kingdom. <sigh>
For me the Baklunish lands are one of the most intriguing regions of the World of Greyhawk. I always though it was cool that the Baklunish once dwealt east over the mountains, but became refugees from the Invoked Devasation cataclysm. And then reeked their own devastation with the Rain of Colorless Fire, blazing an entire region into the Sea of Dust! They didn't get much text in the original 1980 Gazetteer, but what did. The best source for the them I've read is the Living Greyhawk Gazetteer. Taking into account all Baklunish content from the poltical details to the text on the Muquallad Consortium, there's a about 10 pages in the LGG. IMO plenty enough to drop a suitable adventure in any of the 6 politys and run with it.
I always felt that the city of Ekbir was inspired by the city of Basra of the Golden Age of the Caliphate, and that the Tusmit's capital of Semur was somewhat analogous to Bagdad. There's no doubt that it was meant to be a uniform area, as Baklunish is spoken throughout all 6 Baklunish politys. So is Common, but that's more of a D&D norm/thing. As well, even though demi-humans are present they never comprise more than about 21% of a population and usually only about 4%. Were a DM to want a Human-only campaign, it could be done easily by just subbing demi-humans with other Human cultures.
Well going by the original WoG map they were, but going by Anna Myers newer online map...Bold Baklunish mariners in the summer months could sail north on the Dramidj Ocean into the Icy Sea, then eastward and southeastward around the lands of the Ice Barbarians to the Solnor Ocean. It'd be one heckuva a journey though! A fun campaign could be the Damidj Ocean to Icy Sea and then into Blackmoor Bay.
Anyhow...I've thought more than once about running a campaign in Greyhawk with OSE, or maybe even adapting it to True20 or 13th Age.