Here Oliver Cowdery initially wrote Northwards in the original manuscript, but then he erased the final s (an immediate correction). The corrected reading in 𝓞 is consistent with all adjectives and adverbs ending in -ward(s) that specify a cardinal direction: 44 other occurrences of northward, 20 of southward, and 3 of eastward, but none ending in -wards.
There has been a similar tendency in the text for Oliver Cowdery to add s to the word forward (for discussion, see under 1 Nephi 8:30). The tendency to add the s may be prompted by the adverbial form towards , which is much more frequent than toward in the earliest text of the Book of Mormon (see the discussion under 1 Nephi 5:22).
Summary: Maintain in Alma 52:2 northward, the corrected reading in 𝓞; there are no instances of northwards (or the related directional forms eastwards, southwards, and westwards) in the Book of Mormon text.