Here in the printer’s manuscript, Oliver Cowdery started to write the more frequent Book of Mormon expression in which nation precedes kindred. (There are seven occurrences of the phrase “every nation kindred tongue and people” in the Book of Mormon text; see the discussion under 1 Nephi 5:18.) In this instance, Oliver immediately corrected his error by crossing out “& Kindred”, supralinearly inserting Kindred before Nation, and then supralinearly rewriting the ampersand that he had originally crossed out:
The level of ink flow for the correction is unchanged.
We should not assume that the occurrence of the and between nation and kindred was due to the now-familiar language of the book of Revelation:
Rather, Oliver Cowdery’s initial and between nation and kindred was probably due to the fact that in Mosiah 3:13 the word nation was followed by an and in his copy-text, the original manuscript (reading presumably as “to every Kindred Nation & tongue”).
The conjoined phraseology with the order “kindred(s) / nation(s) / tongue(s)” occurs only one other time in the Book of Mormon, but unlike Mosiah 3:13 this other example includes the word people in the conjunctive noun phrase:
And unlike the normal word order, people comes first in this other passage. The fact that people is missing from Mosiah 3:13 and that the word order differs from the most frequent order in the text suggests that the corrected reading in 𝓟 (“to every kindred nation and tongue”) is the original reading, or at least the reading of the original manuscript, no longer extant.
Summary: Retain in Mosiah 3:13 Oliver Cowdery’s corrected reading in 𝓟 (“to every kindred nation and tongue”); the uniqueness of the corrected reading argues that 𝓞 read this same way.