The 1837 edition introduced the relative pronoun who in place of the original which. This change may not be due to Joseph Smith’s editing for the 1837 edition since it was not marked by him in the printer’s manuscript. Elsewhere in the Book of Mormon text, which is generally retained when it postmodifies nation(s):
In one of these cases (Alma 37:25), which was accidentally changed to that as Oliver Cowdery copied from 𝓞 into 𝓟 (but not to who, it should be noted). Elsewhere there are three cases of “nation(s) that” in the original text:
But there are no occurrences of “nation(s) who” in the original text. Thus the 1837 change here in 2 Nephi 25:22 is anomalous. The critical text will maintain the earliest reading in all these cases, either as “nation(s) which” or as “nation(s) that”. For further discussion of which versus who, see under which in volume 3.
Summary: Maintain the relative pronouns which and that for nation(s), including here in 2 Nephi 25:22 (where the 1837 change to who may be accidental).