However, if Gen 8 is a Kanto/Johto sequel, then we could see seasons return there. The part of Japan they're based on has a moderate four season climate (ie. hot, humid summers and slightly cold, unstable winters -- very similar to the Mid-Atlantic US, IMO), and we've even seen hints of "seasons" in HGSS with the fall colors in north Ecruteak.
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I'm not sure how you feel, but I really want Gen 8 to return to Japan, and not just for Sinnoh remakes. Unova was okay, but the other two non-Japanese regions (Kalos, Alola) have largely been letdowns, albeit in different ways. Kalos had nice aesthetics and a great Pokédex, but a painfully generic story and dumbed-down gameplay, while Alola had an interesting story and memorable characters, but was also an awfully-designed region overloaded with poorly-implemented gimmicks (Trials, Ultra Beasts, Z-Moves, etc).
More importantly, I also feel that every new gen being a hard reset in a far-off country has destroyed whatever sense of continuity this franchise once had. When you discount the PWT and Battle Tree, the number of returning characters we've had since Gen 5 has been minimal, and with the lone exception of Sylveon, we've now gone three generations in a row without a single new pre-evolution or evolution.
This lack of continuity has also carried over into the anime, with each new saga since Gen 5 (BW, XY, SM) feeling more isolated and standalone compared to OS/AG/DP. Outside of Ash and the TRio (who both get a hard reset in personality and dump every Pokémon besides Pikachu/Meowth/Wobbuffet with each new gen), the cast gets completely replaced with every new region, and past character cameos have been minimal (with XY having none at all).
Going full reboot worked as a one-off thing for Gen 5, but it made far less sense for Gens 6 and 7, especially when GF clearly wanted to go in a more nostalgic direction with those gens compared to Unova. Enough with the reboots and far-flung regions. I'm ready to return to Japan and see some continuity in this franchise again.