It was a nice read, but there are also many flaws in your story.

For one, Link and Zelda were pretty much forgotten in the story. For all that fuss you made over the Tetraforce issue, you barely acknowledged the existence of the other two Bearers in this story-Zelda made her debut on one chapter only to be killed off too soon, and Link only showed when Zelda was sick and when it was the final battle. You could've done something more with them, especially since they have a (possibly) deeper level of connection with Allisima, but they ended up getting the short end of the stick instead.

And as for your OC, while actually a pretty decent character, was just...strange. I mean, the "Satou Michiko' name just randomly popped up in the last chapter, and I didn't even know who that was until the last few paragraphs. And I think that you could've also emphasized a bit on Allisima's heritage, like give her some Twili magic or something. You could've done with fleshing out her character more instead of quickly diving headlong into the plot without giving the much-needed exposition on the characters.

And as for this "Hope" character, what happened to her? She appeared on one scene, and quickly became forgotten. Is she just going to remain a forgotten plot bunny, or is she going to make a reappearance in the sequel?

Those are just some things I'd like to point out. Some of the other issues I have with this story are mostly personal opinions. But I actually enjoyed Allisima, since she's one of the few OCs I've seen that don't turn out to be complete Mary-Sues, and her being at a younger age than usual made her a refreshing character compared to angsty, teenage girls. The story...leaves much to be desired, but if you fix some things, like the issues I've pointed out, it'll become easier and more enjoyable to read.

If there are any grammatical errors on this little ramble, kindly ignore them, as English is not my first language. Hopefully I helped with this criticism! :)