Equivalent for "née" in spoken English
Solution 1:
How about simply translating née into English, giving born?
"Jane Smith (born Doe)"
For an example of usage, see this web page
Additionally, see this definition (1b): used for saying that someone had a particular condition, personal quality, name, or social status at the time when they were born [...] e.g. Elton John, born Reginald Dwight.
Solution 2:
In Irish, Ní means ‘daughter of’ and Mac/de means ‘son of’. So a name such as Mary Burke in Irish is Maire Ní Buirce, which means Mary daughter of Burke, and Sean de Buirce means John son of Burke. It can also be used in this context — e.g., Mary Murphy Nee Burke: Mary Murphy daughter of Burke.
Née is so well used in everyday life now that formerly, daughter of, born, or any others will not express what you’re trying to say well enough. You won’t get the same effect no matter what the direct translation — I agree with Urbycoz: stick with Née.
Solution 3:
Apart from née itself, I'm not sure if there is any word that conveys exactly the meaning you want. Instead of formerly, you could use originally or previously but they mean exactly the same thing.
The only thing I can think of is formerly or formerly known as, but those almost sound like something you would say about a criminal to me.
I understand what you mean but I don't think there is much that can be done about it. Apart from when a woman gets married, it's unusual for someone to change their name and even though there might be a perfectly reasonable explanation it's human nature for people to think there might be something odd about it - be that eccentricity, criminality, or something else.
In your speech or news report, you could elaborate on the reason behind the change of name. This would be justified if the change of name is relevant to the matter at hand. If it's not relevant, just leave it out.
Solution 4:
I don't think née works in this context, because it sounds more like a negation.
Fair enough, but the spoken English form of née remains, née.
But if you've a personal dislike for it, by all means just translate it; "…who was born…".