The ones that God has spoken to, yes. See verse 11 again, they write the words the Lord speaks to them.
Sorry, but your BoM says ALL; HE'll speak to ALL...
2 Nephi 29:
10 Wherefore, because that ye have a Bible ye need not suppose that it contains all my words; neither need ye suppose that I have not caused more to be written.
11 For I command all men, both in the east and in the west, and in the north, and in the south, and in the islands of the sea, that they shall write the words which I speak unto them; for out of the books which shall be written I will judge the world, every man according to their works, according to that which is written.
12 For behold, I shall speak unto the Jews and they shall write it; and I shall also speak unto the Nephites and they shall write it; and I shall also speak unto the other tribes of the house of Israel, which I have led away, and they shall write it; and I shall also speak unto all nations of the earth and they shall write it.
13 And it shall come to pass that the Jews shall have the words of the Nephites, and the Nephites shall have the words of the Jews; and the Nephites and the Jews shall have the words of the lost tribes of Israel; and the lost tribes of Israel shall have the words of the Nephites and the Jews.
14 And it shall come to pass that my people, which are of the house of Israel, shall be gathered home unto the lands of their possessions; and my word also shall be gathered in one. And I will show unto them that fight against my word and against my people, who are of the house of Israel, that I am God, and that I covenanted with Abraham that I would remember his seed forever.
I believe Jeremiah was not only a prophet to Israel, but also to us, the gentiles, and all who seek God's word. So I find no difference in what Nephi is saying here. His prophets speak for the whole earth, and who knows how many he has had, only he knows.