agreed, for east and west border this would be great. for north and south borders, assuming u go to north border, and ur x value would be negated like on the north border x400 to x-400 or x-400 to x 400 same for south as that would be way more realistic then going from north to south or south to north. if this map was cylindrical east and west would join not north and south so irl thats how it would work.
basically the effect of going to a border(wether its north south east or west) would tp u to the opposite x value AND change the direction youre facing by 180 degrees or turn ur face and body in game around. that would be extremely easy to implement and make it work exactly like irl