Magitech Armour on FFVI (okay Terra is there too, but you can hardly see her). I think it's Golbez on the DS remake of FFIV. The Emperor on FFII. Looking more recently, FFXV is definitely not Noctis.

Also it turns out that the FFXIII cover is Cocoon, but it also features Fang and Vanille apparently. Also not MCs.