You’re not late, you can always ask me anything you’d like about my aus! :D And yes, you are correct: Eichlyse can manipulate Ariney with her Nen, just like Illumi can manipulate Killua with his Nen. If Illumi is using Needles, than Eichlyse can apply her own Nen to those Needles and Illumi will throw them for her at daemons. Nen by daemons will only work against daemons, they will not work on humans. But she doesn’t always need Needles to use Nen, just like how Illumi can change his appearance for a certain amount of time without the help of his Needles. And sometimes using Nen against a human alone is enough to make their daemon submissive.