
Let me first preface that any answers you received on that Mateus discord as well as any answers you get here (including my own) are purely speculative. There are no canon answers to your questions yet.
Is Hydaelyn evil? She's not been presented that way really, but good and evil aren't always black and white and some may interpret this concept differently. There are many people I've noticed who look upon any supernatural entity that exerts its interests above a person's own free will as outright evil and malicious (usually in reference to elementals). Others look to how most FFs in the series paint any deity and its accompanying religion as the end boss / true bad guys.
I choose to look at the disciples of Hydaelyn, opposed to the disciples of Zodiark. The latter purposefully sow chaos, destruction, and death - while the Crystal Bearers who rise up when Calamity is nigh try to mitigate the tide of destruction.
As for why Hydaelyn chose Minfilia at that moment, I don't know. Maybe we'll find out eventually, maybe not.
Why Minfilia as Hydaelyn's Chosen though? She seems like the obvious choice. She's more than just an Echo wielder, she's one of the first. She witnessed the Battle of Silvertear Skies firsthand where the Echo first sounded. She founded the organization which united and protected the Echo wielders, well before the Students of Baldesion began their own research. Even her title, Antecedent, a word meaning prior to, preceding, or the one before could be taken to mean she is viewed as the first Echo user, though that's just one interpretation. She, like the WoL, had heard the Mother Crystal before and had a strong connection with her. Even Elidibus and the Ascians went after her.
Beyond that, /shrug!
Is Hydaelyn evil? She's not been presented that way really, but good and evil aren't always black and white and some may interpret this concept differently. There are many people I've noticed who look upon any supernatural entity that exerts its interests above a person's own free will as outright evil and malicious (usually in reference to elementals). Others look to how most FFs in the series paint any deity and its accompanying religion as the end boss / true bad guys.
I choose to look at the disciples of Hydaelyn, opposed to the disciples of Zodiark. The latter purposefully sow chaos, destruction, and death - while the Crystal Bearers who rise up when Calamity is nigh try to mitigate the tide of destruction.
As for why Hydaelyn chose Minfilia at that moment, I don't know. Maybe we'll find out eventually, maybe not.
Why Minfilia as Hydaelyn's Chosen though? She seems like the obvious choice. She's more than just an Echo wielder, she's one of the first. She witnessed the Battle of Silvertear Skies firsthand where the Echo first sounded. She founded the organization which united and protected the Echo wielders, well before the Students of Baldesion began their own research. Even her title, Antecedent, a word meaning prior to, preceding, or the one before could be taken to mean she is viewed as the first Echo user, though that's just one interpretation. She, like the WoL, had heard the Mother Crystal before and had a strong connection with her. Even Elidibus and the Ascians went after her.
Beyond that, /shrug!