Depends which you mean. Replayable as in "I want to play this entire game again"? No, Gens 1-3 are way better for that. Replayable as in "I want to continue playing this postgame"? No HGSS and B2W2 are probably the top. Sword and/or Shield are probably alright in the former category as far as team composition goes, given the Wild Area options, but the same could be said for XY and SM having way too many fucking Pokemon, XY especially, and the experience isn't that smooth. On the other hand, if you're talking postgame content the only major thing to do is Raids, which are either RNG NPC bullshit, or rely on other people which is fucking tenuous at best. That having been said, LAN mode will keep raids alive as long as the internet exists at all, which is more than I can say for some of the best parts of the Gen 6 games.
