Just a random shower thought curiosity I have no clue how to effectively research.
What is the “moon flip”?
The moon as viewed from the northern hemisphere looks upside-down as compared to the moon as viewed from the southern hemisphere, and vice versa. The same is true of constellations that are visible from both hemispheres.
From the tropics (say, south of Egypt), the sun, moon, and planets appear for an increasing fraction of the year in the northern sky rather than the southern. The Greeks observed this, although I can’t think of any who called explicit attention to the orientation of the moon with respect to the horizon. But while they believed the moon to be fixed to a rotating sphere which tilted with respect to the earth over the course of the year, the moon’s observed orientation would have matched this model and they wouldn’t have thought it especially notable.