Chatot A+ -> A The drops were very unkind to Chatot. Liepard, Alolan Dugtrio, and Lycanroc all outspeed and OHKO it, with the latter two also taking a hit from Choice Scarf (ADuggy has to fear Heat Wave) and the former being able to use Prankster Copycat or Thunder Wave to cripple it regardless. Crustle can tank a hit and OHKO it easily while Chatot's Specs set also lost Stoutland and Ursaring to revenge kill while not gaining anything else. It would drop more but the loss of two major competitors as Normal-type breaker lets it keep its A rank for now.
Mawile A+ -> A Mawile was A+ mainly for being one of the few absolute counters to Stoutland. Now that that's gone, it should drop. Its new Shuca Berry set does fair well against Pokemon like Lycanroc and it does have a good matchup against Liepard, but it should drop.
Beheeyem A -> A- Beheeyem does not like Liepard and Crustle dropping at all. It was already struggling to keep up with the rest of A, but now it simply cannot keep its rank. While it does appreciate Musharna getting banned, it really suffers from how common Grumpig is currently s at the moment.
Ninetales A -> A-
Rapidash A -> A- Both of these heavily dislike drops like Alolan Dugtrio, Lycanroc, and Crustle as well as how common Grumpig is at the moment, so both should drop down one subrank.
Rotom-S A -> B+
Oricorio-E A- -> B+ These also also both suffer heavily from drops like Lycanroc and Crustle while having to compete with other Electric-types like Rotom-Frost and Manectric. They do not differentiate themselves enough and are thus booted out of A.
Raichu A- -> B+ The addition of several Pokemon that threaten it like Liepard, Lycanroc, and Lurantis make Raichu considerably worse. Since it was already at the bottom of A-, it is now dropping to B+.
Smeargle A- -> B+ Sticky Web got much worse with Ursaring and Stoutland leaving the tier and Smeargle now faces competition from Shuckle (though it is generally better), so it drops down a subtier.
Cradily B+ -> B Increasing popularity of Fighting-types, Torterra becoming more common, and the departure of two Normal-types make life hard for this. It was already tough to use over other Rock setters but now it really struggles to fit on a team, so a drop to B is appropriate.
Fraxure B+ -> B With how common Choice Scarf Rotom-Frost still is, Fraxure really struggles to actually sweep. This in addition to struggling to set up with a meta as offensive as this, being unable to break Togetic stall, and fearing Liepard's Encore means that it no longer deserves a B+ rank.
Huntail B+ -> B With an abundance of Scarf Electric-types, fat Grass-types, and bulky Water-types, Huntail just struggles to do much in this meta. It's too frail to consistently set up and tends to drop to priority or a Scarfer even if it does. Unfortunately, it doesn't really have a place in B+.
Roselia B+ -> B A Grass-type that fails to check Ground-types will struggle to find its place currently. Especially if that Grass-types major role is setting Spikes and Crustle drops. Roselia shouldn't stay in B+.
Servine B+ -> B With more competition from Lurantis and Silvally-Grass becoming more popular, Servine doesn't set itself apart enough to maintain such a high rank.
Simisear B+ -> B The addition of Lycanroc and Crustle make life hard for Fire-types and Simisear is no exception. Dropping down.
Dwebble Usually Useless -> Unranked We have Crustle now