Brant A. Gardner discusses the use of "Christ" in the Book of Mormon; argues that the phrase "his name shall be Jesus Christ" in 2 Nephi 25:19 is a translator's gloss.
Brant A. Gardner, Second Witness: Analytical and Contextual Commentary on the Book of Mormon, 6 vols. (Salt Lake City: Greg Kofford Books, 2007), 2:160
Translation: “Christ” is a title, not a name. Nephi understood that distinction, for he later used the title correctly: “And as I spake concerning the convincing of the Jews, that Jesus is the very Christ, it must needs be that the Gentiles be convinced also that Jesus is the Christ, the Eternal God.” nevertheless, 2 Nephi 25:19 somewhat awkwardly uses “Christ” as a name and also uses “Messiah” as a title in the same verse. It is hard to understand what underlying text would have yielded both the anglicized form of the Hebrew word and the Anglicization of the Greek form of the Hebrew word in the same sentence. A simpler explanation is that Joseph Smith added the phrase “his name shall be Jesus Christ,” rather than making an exact translation of the text.