It's rather well-known that video game maps consisting of (a) a square or near-square world layout, and (b) wraparound in both North-South and East-West dimensions cannot be represented by a spherical planet-shape. It's also become near-conventional wisdom that said planet must be a torus or "donut" shape.
Point A is rubbish. Video game maps are programmed as square or rectangular maps, but these are for progamming simplicity only. The world the game designer imagined when creating the map was more likely than not concieved with our own world as a template. Most feature tropical areas near the equator and pine barrens at higher latitudes giving way to ice and snow at the poles.
I think the better way to imagine this all is that the display you are looking at is a rapidly reprojecting flat surface map representing a spheroid shaped world.
Yes, if you were to attempt to stretch the rectangular or square map data straight from a game onto an appropriately sized spheroid there would be either distortion or blank space, but that does not mean that the game map is from a non spheroid world.
The fact that some games allow you to travel from south to north instead of having you end up heading north on the opposite side of the world is no different than the reason you can't climb mountains in many games or go swimming in the ocean. Programming limitations and awkward gaming mechanics.