Wie natürlich klingt das „either“ in diesem Satz?

Is there any perceptible difference between having "either" and omitting it?

In my opinion, the sentence would mean the same with or without the "either". Both versions sound natural to me.

It doesn’t sound strange anymore if I read it as, “Would you please speak either Chinese or Russian?” But how does it sound if the sentence is to inquire whether the person spoken to knows Chinese or Russian, and is not necessarily asked to speak either one of them? This is what I assumed it was supposed to mean when I asked my question.

First of all I should point out that I adopted the sentence because it was grammatically correct, so I didn't change it.

2. When would I use "either"?
I am about to hire you as a foreign correspondent and you will be posted somewhere on the Russian/Chinese border. Our company has a foreign language requirement to make sure that our correspondents know at least one of the local languages. So "Can you speak either Chinese or Russian" means that you have to know one of these languages but not necessarily both.