Well, with 3 against 1, I’d certainly recommend dropping the [ἐξ ἧς] μίξεως and render it [ἐξ ἧς] γυναικός. It’s a good point for discussion, but no reason to be radical in a book of extracts.
That said, I’ll still advocate for it as correct. MattK’s contrastive topic statement (using “topic” in the CGCG technical sense, and not how I was using it) is contradicted, I think, by the fact that the author doesn’t start out fronting the women. We can look a couple of sentences up to see the focus switch from marriage to adultery with μίγνυται δέ. The women, when they begin to get focus serve almost as labels to the adultery. Our author’s (who is the author anyway?) organization is like this:
Description of Zeus’s first union, a marriage, with a long description of why Zeus chose this type of union to be first:
ἐν πρώτοις … τὸν ἀναμάρτητον γάμον ἐπορίσατο. Additional information follows, that it’s with his sister, Hera. The author’s topic is why all these unions are beneficial to mankind, and he tells us ἐξ ἧς Ἥβη τε καὶ Εἰλείθυια ἐγένετο.
Next he describes the second non-adulterous offspring. Μῆτιν should be Ἀθήνην (the product of Zeus ἀποκυίσκει, χωρὶς τῆς πρός τινα μίξεως). Interestingly for our thread, I guess that some copyist apparently thought that paramours were being listed, not unions, hence the change. [The other typo was εἰμα for Ἱμαλίᾳ, which is probably just down to bad handwriting/eyesight.]
Now the author does the first fronted μίγνυται in a sentence that seems very broken: ἔτι δὲ μίγνυται ἀδελφῇ τῇ ἐξ Οὐρανοῦ καὶ Θαλάσσης αὐτῷ γενομένῃ ἀπὸ τῆς Κρόνου ἐκτομῆς, <ἐξ ἧς> Ἔρως καὶ Κύπρις, ἣν καὶ † Δωδώνην λέγουσιν. I’d personally throw out everything starting with Ἔρως… calling it all a marginal intrusion. λέγουσίν [τινα] Δωδώνην doesn’t seem a natural use of λέγειν. I dunno though. If the sentence is fixable, ἥν seems to refer Διώνη (to be added in at the beginning?), which would contradict my theory.
The we get another μίγνεται δὲ… This (and probably the previous) are fronted because he’s now describing the adulterous unions, having already described the non-adulterous unions. Based on this fronting, MattK’s argument can now be made into a pro-ἐξ ἧς μίξεως argument. And following this sentence, the author now fronts the names of the females in the nature of labels for these unions, not the information that he is most interested in.
But you don’t have to take my word for all this. The author tells us exactly what his subject is in XII:
…ἄρξομαι τὰς ἐνίων μηνύειν κοινωνίας…
…ἄκουε τοίνυν αὐτοῦ τοῦ μεγάλου Διὸς … τὰς διὰ τῆς μεταμορφώσεως λανθανούσας κοινωνίας…
Why is he on about it?
…αὐτίκα γοῦν τὴν λεγομένην μοιχείαν πρᾶξίν τινες ὑπειλήφασιν εἶναι κακήν, καίτοι καλὴν κατὰ πάντα ὑπάρχουσαν…
Seems like a nice subject for Ὁ ἐρῶν to τῇ ἐρωμένῃ.