The original manuscript is not extant here. Based on spacing between extant portions of the original manuscript, the slightly longer remove fits better than move, but either is possible. As he was copying from 𝓞 into 𝓟, Oliver Cowdery wrote “to move the cause of diseases”, then later corrected move to remove by supralinearly inserting the re with somewhat heavier ink flow. This correction was probably the result of proofing 𝓟 against 𝓞; the error move was probably due to the visual similarity between move and remove. The verb remove makes the best sense here in Alma 46:40 and should be retained. For another case where the Book of Mormon text seems to have replaced remove with move, see under 2 Nephi 20:13.
Summary: Accept in Alma 46:40 Oliver Cowdery’s corrected reading in 𝓟, remove, rather than the initially written move; his correction appears to have been done while proofing 𝓟 against 𝓞 (which is not extant here for this part of the sentence).