Oliver Cowdery initially wrote to in the printer’s manuscript, but later he changed the to to unto by supralinearly inserting the un and adding an insert mark (all in considerably heavier and darker ink). Elsewhere in the Book of Mormon text, “give ear” can be followed by either to or unto:
None of these other examples show any variation between unto and to. Theoretically, either preposition is possible in 2 Nephi 25:4. In modern English, to is the expected form, so Oliver’s initial to in 𝓟 was probably an error based on his expectations. His later correction in heavier and darker ink was probably made when he proofed 𝓟 against 𝓞.
Summary: Retain in 2 Nephi 25:4 the preposition unto, the corrected reading in the printer’s manuscript and the probable reading of the original manuscript (“give ear unto my words”).