The job quests for each of these three new jobs will be located in Ishgard.
With this being true now, the musketeer's guild in Limsa is useless. I am surprised the guild wasn't willing to train adventurers in the way of the pistol and musket. Especially seeing all of the muskets racked up in the guild and inside the Maelstrom headquarters. Then, there is also the Lominsan guards, captains and pirates that all carry guns.

I am happy for Machinist being included in Heavensward but rather disappointed at the musketeer's guild serving as simply a decoration for all of these years.