Is accenting ‘o’ instead of the pronoun deliberate? It sounds weird, especially after learning Russian. And also since o nas sounds awkwardly like Hebrew אונס ónes ‘rape’.
It is a sentence accents, you can change them,
but I tried and when not trying to accent anything o_nich o_nas work like one word with normal Polish accent, and normal Polish accent is second syllable from the end
The particles are accented together with the words they have been attached to. This means they are often not accented, but if the following word is only one syllable long, then the particle is accented instead.
I had the sentence to listen too, and the first time did not check the slow, because it seemed evident that it was "mówi o nich" the ę is heard only in the slow version. Is that normal, I guess in a conversation it would be clear who is speaking. I would like to know if the polish are dropping the last syllable, and when. thanks.
No, Polish generally pronounces everything that is written, apart from really few exceptions (and pronouncing final -ę as -e). So absolutely no syllable dropping.
I think I can agree that the female voice sounds more like "mówi" and the male one at least could be mistaken for "mówi". I disabled the audio exercises, so at least no one will get the 'type what you hear' exercise.