
Hydaelyn is weird, because when you mention her all the (major lore) NPCs speak about her in, like, hushed whispers. Gasp! You saw the Mothercrystal! So on the one hand: they recognised her from your description (a towering crystal that spoke), so obviously her existence is A Thing to non-Echo users. But on the other hand that doesn't tell us anything about how well known her existence is or if she's worshipped as a god, at all.
I do think that it's fairly evident that even if she is worshipped, the Scions of the Seventh Dawn (and before them, I'm guessing, the Path of the Twelve) are her most forefront worshippers. I mean, she's not as much of a practical god as the others. You pray to Thaliak to make wise decisions, Nophica for a bountiful harvest of materials, Byregot to craft your wares well, Llymlaen to navigate the sea safely, Oschon to do the same for the land, Nald'thal to have fruitful trades once you're there, and Menphina to ensure you have a loving spouse to come home to after all of it. You can even - less tangibly - pray to Althyk for a good long future, Nymeia for luck, Rhalgr for the destruction of your enemies, and Azeyma or Halone for revenge or protection...
What's left to pray to the Mothercrystal for?
I do think that it's fairly evident that even if she is worshipped, the Scions of the Seventh Dawn (and before them, I'm guessing, the Path of the Twelve) are her most forefront worshippers. I mean, she's not as much of a practical god as the others. You pray to Thaliak to make wise decisions, Nophica for a bountiful harvest of materials, Byregot to craft your wares well, Llymlaen to navigate the sea safely, Oschon to do the same for the land, Nald'thal to have fruitful trades once you're there, and Menphina to ensure you have a loving spouse to come home to after all of it. You can even - less tangibly - pray to Althyk for a good long future, Nymeia for luck, Rhalgr for the destruction of your enemies, and Azeyma or Halone for revenge or protection...
What's left to pray to the Mothercrystal for?