It might be Eliyah and Elisha, and again, it looks like it could be John, of revelations, Yahuchanan (Yahu is kind).
We don't really have to worry about this though. Only thing to worry over about this subject is, not being discriminating and open to truth, proving everything anyone ever 'teaches' or tells us. We have to prove all things, that is the command.
and love the truth, and ferret out all the MANY LIES.
And these two witnesses will be telling the truth, of Yah, and which Yahushua re-told and re-taught again, while he was on earth, and again, the whole world will hate them, as the leaders and powerful people hated Yahushua.
But he did strike a chord with the many poor and downtrodden people, did he not. That is what the leaders all HATE.
so, main thing, is study up, prove all things now, while you still can, and when they appear and when they speak, you will already know if it is truth or not!
it's not easy. but it is commanded, and expected of us.
We need to be scholars. Read the Two Babylons by Alexander Hislop for one thing and that is not easy, or light, but very very necessary.