No true gods?

[Hinoto-no-Ryuji]

I'm not so sure the Twelve can be properly considered Primals since, as far as I can remember, Primals are very specifically a summoned instance of a deity. Even Garuda, Ifrit, Titan, and their ilk aren't Primals until summoned; they're just a concept worshipped collectively, like the Twelve. So the Twelve were Primals briefly when Louisoix did his thing, but can't really be considered such outside that particular instance.

As such, the Twelve "exist" in the same way everything but Hydaelyn seems to: sentient beings can give physical (well, aetheric) form to the concept of them, but that concept is what shapes them. They have no actual, pre-determined form.

[Berethos]

So the Twelve were Primals briefly when Louisoix did his thing, but can't really be considered such outside that particular instance.

I'll have to double check, but I believe they didn't even reach Primal stage then - what Louisoix did was use the prayers and concentrations of aether present - collectively called the power of the Twelve due to the way it manfiested - to power the act of weaving the most powerful sealing enchantment ever attempted.

So they didn't actually manifest as primals at that point...but whether the power wielded by Louisoix was born of belief and aether concentrated or a boon granted by the actual Twelve (who, as others have mentioned, may or may not actually exist and we don't know for sure one way or the other yet) we can't say for certain.

Yet.