All (canon) Dragoons are Ishgardian knights. Not all Ishgardian knights are Dragoons. But yes! We do see some Ishgardian NPCs in the main story using PLD skills, and Aymeric's sword looks a bit similar to the Curtana. It wouldn't surprise me if there are Temple Knights in Ishgard's ranks who are trained in skills and spells similar to the Sultansworn, but it would be nice to have something concrete on that point.
Yvelont Navarre
Parn Paparn
IC Blog for Yvelont: http://never-your-pawn.tumblr.com
OOC Blog: http://navarre-again.tumblr.com
Parn Paparn
IC Blog for Yvelont: http://never-your-pawn.tumblr.com
OOC Blog: http://navarre-again.tumblr.com