Are crossover events canon?

[Belhi]

There's no Shantotto in XIV lore. There is a Shatotto, no "n" in there, who was supposedly the original owner of the Stardust Rod. That's all the information we have on her.

... it is quite obviously a shout-out to Shantotto, but it's not the genuine article. Probably maybe.

Oh I never noticed the n was missing.

We do know more about Shatotto from the BLM quests since you literally using her Soulstone, which you need cause channeling Black Magic without a proper BLM soul stone is extremely dangerous

as in the magic can literally cook the caster from the inside out.

Shatotto was the one who first devised the method which was the basis for Black Magic. She is basically the originator of Mhachi Black magic.