Yes, up to some extent. Although whether the Wenuts and Serpentine creatures are literally children of Apep remains unknown, they do have a link that remains to be explored. As we know, Apep contains the "Heart of Oasis," which, as we know, contains concentrated forms of energy that can take the shape of different lifeforms. This particular phenomenon was displayed in Nahida's second story quest, which we must complete to unlock Apep's domain.