Here we go. Wandersong deserves its characters to be morally scaled, and at least Audrey Redheart is (as Pure Evil). Any text from her Villains Wiki page in this proposal was written by me.
What's the work?
Wandersong is a usually relaxing video game about a singing bard who finds out that the decay of the world is occurring and that the final part in Eya's cycle of death and rebirth is nigh once again. They set out on an adventure to meet the Overseers and get them to tell the Bard their fragments of the Earthsong, a song said to repair the world. Along the way they meet Miriam, a curmudgeonly young witch who helps them in their quest and becomes friends, and Audrey Redheart, the antagonist whose goal is to kill the corrupted Overseers and bring about the end of the world.
Who's the character?
Eya is the immortal goddess of creation. She is the overarching antagonist of the game. She started the cycle. The cycle goes: Eya would, through a special song, create a new pure universe, with seven Overseers, cosmic entities which keep stability in regions of the world. Over the ages, the world becomes old and dissonant, causing the Overseers to start to corrupt. Eya sends her messenger, Eyala, to choose a "hero" who will slay the corrupted Overseers and, unknown to the hero, destroy the entire universe by killing all of them. After this, she sings the creation song again, and the cycle begins anew.
She sent Audrey Redheart as the chosen "hero" to kill the Overseers and thus destroy the universe. She did the same thing many times in the distant past with different chosen ones. Working for her is Eyala, a divine messenger who helps the heroes in their quest, who helps both Audrey and the Bard in pursuing their goals.
What makes her heinous? Does she pass the heinous standard?
She is responsible for choosing many heroes to kill Overseers and destroy universes as part of the cycle. The universe's imminent destruction is treated with weight and near the end of the game things are clearly about to end and it's treated with sadness. While the past universe destructions may be considered offscreen villainy, the present one, where she gave Audrey Redheart her quest and fully enabled her crimes, is definitely not. She sets the heinous standard alongside Audrey.
What are her preventions?
Eya is insufficiently characterized. She is only talked about and never seen. Nothing of her personality is truly known and the citizens talking about her don't give a clear picture. This is the main reason she is Inconsistently Heinous.
Eya is a goddess who creates the universe and only sends someone to kill the Overseers and destroy it when the Overseers get corrupted and the world gets discordant (and people suffer from the world being discordant, as seen in its worsening symptoms throughout the game), and makes the world fresh and new. People think she sees destroying it as a mercy kill. Eya seemingly operates on a different scale of morality where a peaceful uncorrupted world is good even if it involves destroying the old one, and most people see her as a kind and loving goddess despite this. Nothing indicates that she still feels a desire to destroy the world after the Bard and the rest of the world repair it through the Wandersong. But things regarding her are generally unclear, but the friendly Eyala who helps the Bard save the world (and also helps Audrey try to destroy it) likes serving Eya.
Verdict
Yes to Eya.