I personally feel its 99.99% possible a holy for paladin.

Paladin had holy in Final Fantasy XI...

Nothing can ever be "confirmed" until its official, but just take a look.

(I would be very pleased if it does not consume all MP, and is in fact area of attack)

PLD for sure casts a spell in the trailer, and here is the animation comparison to Holy for White Mage.


PLD holy in stormblood trailer:



WHM holy in game:




PLD zoomed in on a specific part of the animation:



WHM zoomed in on a specific part of the animation:







It isnt war drum, but i am pleased never the less.