but as you pointed out previously, this case may have actually stemmed from Game Freak's laziness. The fact of the matter is though, in-universe, there is day and night. In RSE, they just don't show it for some reason, but time is moving, and there is night as evident by Umbreon
's ability to evolve. In FrLg, such a system doesn't exist in an attempt to emulate the original games, but at least a less cop-out answer would be that "Red is a good little boy who doesn't stay out in the dark" rather than a less-then-explainable "Time is messed up because I say so, because I can't admit game-play-and-story segregation exists, because its internally inconsistent, yet saying time is messed up with no in-universe explanation is consistent"
To say "time is just messed up" as an explanation for the trades between Colo/XD and RSE, and Colo to XD by proxy of Gen III games is to selectively ignore the fact that yes, there is
some internal consistency when it comes to trading between games that clearly don't
take place in the same relative points in time. Pal Park and Pokétransfer were indirect trades, not even trades, but transfers. They have consistency in that the transfer has always been in the past to the future.