As a sibset, those are way too... matchy. Irene and Iris practically sound alike, Ines and Iris differ by only one consonant, and visually Irene and Ines are extremely similar.
I'm not a fan of Ines because I'm never quite sure how to say it (I'm pronouncing this as EYE-nes, is that correct? Or is it EE-nes?), but Irene and Iris are good names independently. Of the two, I prefer Iris.
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