An interesting easy to miss detail has been spotted in an alternate shorter trailer for Sun&Moon:
As you can see, even though Solgaleo has the Sun-Symbol on its forehead, Lunaala has this symbol instead of the Moon-symbol.
And it looks far too reminiscent of the Psychic-Symbol to be ignored.
In part 1 I mentioned that I could see the mascots be dual type, only if they shared the Psychic type due to the cosmic association it has had in the past (Deoxys, Lunatone/Solrock, Elgyem, Psy Gym leaders of Hoenn and especially Kalos). In that case, I expected Psychic/Fire and Psychic/Flying.
But now this info changes it. Since only Lunaalas forhead symbol resembles the Psychic eye, I'm now convinced that Psychic will be Lunaalas core type, having the same importance as Fire for Solgaleo.
Nothing changes in it most likely having a secondary Flying type.
Although I'm sad that the chances for Ghost have dropped tremendously now (while the popular Fairy speculation has no chance at all at this point), Psychic does make sense to fit a more bright aspect of this legendary (weheras Ghost, or Dark, are sort of contradictory to it), better fitting the attack it uses, as well as the Moon thematically being a light-source worthy of rivaling the sun itself. It would also further reassure that the moon-association IS NOT exclusive to the Fairy type, and that Cresselia is justified in being a pure Psychic (there is Musharna who evolves via Moon Stone as well).
Also, the mascots being Fire and Psychic? There is our first GS-homage already.