Royal Transylvania or East Hungarian Kingdom

Neither. The Eastern Hungarian Kingdom died with the Treaty of Speyer; afterwords John Sigismund Zápolya was the vassal Prince of Transylvania. While a surviving Zápolya dynasty might revive the Royal title I don't think it would stick; to much of central Hungary was under Ottoman control for the claim to matter. Nor would a Kingdom of Transylvania be tolerated by the Ottomans or the Habsburgs; both considered Transylvania their vassals and a Kingdom is a bit too high ranking for vassalage.
 
Well I did assume there wouldn't be an OTL Treaty of Speyer.
IIRC John II claimed the royal title and was accepted by the Ottomans as vassal (he needed support against the Habsburg claim).
 
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