First of all I would like to thank Stego Lily for her research and neat answer.
This question regarding Adam and Eve kissing came about as I contemplated a scene in a recent temple video.
It is interesting to review the scriptures where kissing is mentioned. As far as I could see there is no mention of kissing in the Doctrine and Covenants. Kissing is mentioned many times in both the Old and the New Testaments. The kiss where Judas betrays Jesus is frequently mentioned. In the Book of Mormon I can find only two verses where kissing is mentioned. In both verses the reference is to kissing the feet of Jesus.
There is one reference to kissing in the Pearl of Great Price. In the Book of Moses (Moses 7:63) we read
Of course it is possible that when the Lord told Enoch that there will be kissing when the City of Enoch returns Enoch thought, "Kiss? What in the world is that?" But I don't think so. Note also that Enoch was something like the seventh patriarch after Adam, and Enoch knew Adam. So I think kissing was known at least as far back as Enoch, and my guess is it was known to Adam and Eve.And the Lord said unto Enoch: Then shalt thou and all thy city meet them there, and we will receive them into our bosom, and they shall see us; and we will fall upon their necks, and they shall fall upon our necks, and we will kiss each other;
Does the imagery of Moses 7:63 seem familiar to those who have been to the temple recently?