You may not know but not every poster on this thread comes from the same example. From what you write I assume you are referring to multiple choice rather than the example at the top of this page. If no, save my wife was given as one of the required options then they are referring to its use as a preposition.
Save, in English, as a preposition, is used to refer to keeping, excluding, retaining, setting aside. You save your money not because you think it needs rescuing but because you want to keep it. No one thinks you are about to run into a burning building to pull out your money but rather that you are going to set some aside from the money that you normally process.
If you read serious literature, especially British, you will come across phrases where save is used to mean except. eg: all the windows are closed, save the one in the bedroom.
Sinon = otherwise..... or else
sauf = except..... save
After the Norman conquest of England, the French words sauver (to save/rescue/keep/store) and sauf (save/except) were both incorporated into the English language. Although they mean quite different things, both in English and French, the English speakers chose to pronounce them exactly the same. (save)
Most Americans are uncomfortable and unfamiliar with using save as except even though the foundational documents of the English language do use it that way. You should consider it a possibly misleading translation to use save for sauf even though it would be correct.
Some English speakers even seem to be mildly offended if sauf/save is used that way. You can verify the difficulty with using save for sauf by looking at some of the other comments on this page
Technically yes, but that phrase is rarely used in English and has a different meaning and tone (it usually sounds a bit rude, or at least jokingly rude, and it doesn't imply marriage). Ma femme 99.9% of the time would be translated as 'my wife'. For example men I know who live with their girlfriend never ever say 'ma femme' and if you asked them about their 'femme' they might say that actually they're not married.
The accent is one which is typical of the southwest part of France. It is normal. Don't expect that everything is going to be exactly pristine when it comes to the way people anywhere pronounce words. To many people, the accent represented by the male voice is more clearly enunciated than the female voice. Ideally, there should be ten different voices so learners are not tied to one voice.
Came into discussion trying to figure what the sentence meant, conceiving no usage for it. Ok, asked does this guy hang with girls? "Not but his wife""not save his wife""not unless his wife""not without his wife" Never gonna answer "no, except his wife," because you better not pause incase the wife is listening, and we English cant sum up the sentence with the hand gestures that keep the French much safer from each other.