So there was a tier shift, tier shift looks even cooler now:
Scrafty moved from UU to RU: Pretty interesting, the first instinct you might think is Dragon Dance but I'm a little iffy on that, you still get outsped by virtually every scarfer in the metagame. It does outspeed ttar but you have to compromise a lot of bulk just to do it, and I feel scrafty's bulk is what differentiates it from pangoro. Mostly outclassed by Pangoro though cause dds/bus are pretty hard to set up and you aren't even super strong at +1. Could possibly work though.
Gallade moved from OU to UU Gallade is pretty interesting, with Doublade becoming significantly less viable, and Cress now being not nearly as common benefits it sooo much. It still probably won't do much
Kingdra moved from UU to RU I don't really feel that rain is gonna be broken, like there are mons like Ferrothorn and SpD mola that are already pretty common that can stop it. It will be really good though.
Mandibuzz moved from OU to UU I don't see this doing much, yeah it's a pretty cool defoggers but I don't see much reason to use it over something like Skarmory. It might be good though.
Flygon moved from UU to RU Definitely overhyped. This thing is eclipsed a ton by garchomp existing, defog sets sure but I'd probably use Gligar for a ground-type defogger, even with the +10 garchomp still does almost all of what Flygon does better. U-turn is cool yes and is pretty much Flygon's niche but it still is weaker than chomp in a lot of ways.
Alakazam moved from UU to OU I didn't really see much zam at all so I don't know exactly how good it was but on paper it doesn't seem that great, focus sash at least, because of how bulky the meta is. Life orb probably is an awesome set though cause it hits like an absolute truck. Expect this to still see usage though, cause even with it going uu, it still can wallbreak very well with life orb/alakazite but mainly life orb.
Heliolisk moved from RU to UU This is a sad one, heliolisk was an awesome mon. Literally the bane of mola and pretty much every other water type. Probably will still be cool though.
Mamoswine moved from OU to UU Pretty great, not broken at all thuogh cause of all the bulky waters and how common of a type fighting is. Still hits really hard and will be a top tier mon for sure.
Hippowdon moved from UU to OU This sucks for stall teams even though they probably will still use hippo, this thing quite frankly did not die. It set rocks, had a decently strong eq, and has slack off which is amazing.
Fletchinder moved from RU to NU Pretty much outclassed by talonflame still unless you really want 7 more attack on it. Maybe it nets a ko of some sort, but it just seems inferior to talonflame in every conceivable way.
Slurpuff moved from RU to UU This is a godsend for offense, and a curse for it. This is because Slurpuff not only just annihilated offense, but it was also one of offense's best pokemon. Though it is slowly decreasing in viability due to the rise of Garbodor, but it is still a really good mon even with only +5.
Magneton moved from RU to NU Magneton is already an awesome pokemon in the meta, this just makes it entirely outclass magnezone, as opposed to almost entirely outclassing it due to a noticable difference in bulk, but now it is not very apparent. Plus it can run the eviolite set but you lose out on a good amount of power and speed.
Abomasnow moved from RU to UU With mamoswine dropping down, unfortunately this makes mega abomasnow a lot less viable, it has niches with sd and trick room though mainly sd. But Mamoswine is faster, has a stab eq, and tools like icicle spear/crash and whatever its 4th slot will be, rocks or knock off maybe? Freeze dry seems stupid now because literally all it does is hit rotom-w hard. But it isn't as common. I guess swampert and quagsire but I probably wouldn't keep swampert in vs mamoswine, and running it for quag and rotom w seems pretty undesirable. I think it'll still be ok but not nearly as good as it was.
Doublade moved from RU to UU It was ok when it was +10 but now it just seems pretty bad. It's special attack is atrocious, even with eviolite, and it's attack is good but I don't really think it'll cut it because its moves aren't very high power. Swords Dance is nice and all but when you have so many things that can stop you (though hippo going up helps it a little bit)
Cresselia moved from RU to UU I don't think I need to explain why this is good. Subcm sets up on nearly every mon in the tier. It'll still be good but not nearly as dominant. Offense looks so much better now.
Slowking moved from RU to UU Booooo this is stupid, cm slack off sets were so good because it can set up on so much and has 16 pp recovery, av checked fire types well, and specs sets hit incredibly hard. I'd probably always use slowbro for everything but av, and av just seems meh now.
Noivern moved from UU to RU Offense now has a shiny new toy that will be top tier to play with. I think roost + 3 attacks and specs will be the best sets, and tauntroost will be viable too. It is just so fast, it outspeeds scarf emboar, and scarf ttar which are some great assets. Probably the mon I am most hyped for.
Kabutops moved from RU to NU Rain is gonna be a lot better, kinda iffy on whether or not it'll be broken and a lot of oters will touch on that. As a spinner, tops is good because of the fact that it can spin vs nearly every ghost in the game cause of its stabs, top tier mon for sure, rain or not.
Seismitoad moved from NU to RU This makes me salty cause of it leaving nu but it won't have an impact here, other than lessening its niche as a rain sweeper. Defensive sets might be ok but it loses to a lot of stuff.
Whimsicott moved from RU to UU
Peef Rimgar This sucks so much cause Life Orb cott is a great mon, it just provides an insane amount of utility in encore and tailwind/stun spore/etc. . It still will see use though cause of its typing as ability to act as a safety net for offensive teams versus things like Slurpuff.
Pinsir moved from RU to NU I doubt this will have any significant impact on the meta. Things like Scizor exist and scolipede too if you were considering scarf moxie.
Sorry these are pretty barebones, just worked on this for ~3 hours.