Are crossover events canon?

[Cilia]

The odd thing about Shanttoto is there is an important Shantotto in FF14 lore. So canon wise is the Shantotto from the event the Shantotto from the early days of Mhach who decided to go dimension hopping one day or is a different Shanttoto who just happened to be the founder of Black Mage?

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.

[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.