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Are all of the Djinn in Thunder Junction from Tarkir?
(mtgzone.com)
Djinn of Fool's Fall looks a lot like a Tarkir Djinn: 
Smirking Spelljacker and Haughty Djinn don't look anything like the Djinn from Tarkir, though, they're much more human-like in face shape: 
and 
.
Are those ones from somewhere else?
Haughty Djinn was originally printed in DMU, and given that Dominaria has a long history of Djinn going back to Alpha, Smirking Spelljacker is probably from there. Older Djinn didn't really have a cohesive visual identity, but comparing it to djinn from the more recent Dominaria sets, it seems to match up
Out of all the Djinn in Magic, only two other in-universe planes have had Djinn, Ravnica and Strixhaven. Strixhaven is the other possibility, but Spelljacker looks pretty wispy which would align more with Dominaria