(BIG spoiler from the end of the MSQ, encoded in base 64) QSByZWZsZWN0aW9uIG9mIHRoZSBXb0wtQXNjaWFuPw==

My main reason for suspecting this is that Iroha in Maiden's Rhapsody identifies your WoL as the Master (your Adventurer if you played XI). The two must share some sort of connection. Further, the fact that Iroha can be sent to Hydaelyn at all would imply some kind of cosmological connection between Vana'diel and Hydaelyn. Quite possibly that Vana'diel is a Reflection, even.

Certain events in XI could also be Ascian plots, albeit unknown to any of the narrators in XI. The potential calamities in Zilart and Promathia in particular conform to the Ascian modus operandi established in Shadowbringers.