Noah (masculine and pronounced NO-a) is not a stolen feminine name but a traditional evolution in English.
The [x] sound (KH) doesn't exist in English, so it seems logical that the name could had been adapted with the [h] sound at the end, because this one is the sound closer to [x] in English. Since is a soft sound, at the end of the word and on an non-stressed syllable, the change from [h] to no sound would not be surprising at all.
NO-a (pr.) is then not strictly female. It is a case of homophony, simply.