What are the differences between the Echo and having Hydaelyn's Blessing? [Spoilers?]

[Belhi]

The blessing has manifested defensively and offensively. It was the blessing that allowed us to survive Ultima as well as Midgardsormr's final attack and it warded our home from Ascian access. However it also was what we used to make Ultima vulnerable to our attacks at the end of 2.0 (Ultima takes almost no damage before the blessing manifests as a wave of light) and it is what powered our attack that drove Lahabra out of Thancred the first time.

May I ask where have you hear this? o.o The only thing I heared about it was just vague rummons that maybe the WoD used to be a WoL.
Honestly I thought that no info of the WoD was given yet

There was a question somewhere about if Derplander was in our version of Eorzea or an alternate Eorzea and they suggested he and his team were a group of adventurers who had their own adventures and travelled their own path but were in our world. Also at the end of HW Elidibus says 'its time for you and yours to join the fray'. That suggests he has allies who will be turning up to.

So the WoD and his allies could literally be Derplander and his group from the cutscenes.

[Frederick22]

snip

I knew this already. It was mistake then about that he will have his own story. To correct its that " he has his own history and motivations that differ from ours " not that he will