Looking at the new mons introduced to us first:
Naganadel seems rather overwhelming at first. With 121 speed and 127 spatk which is pretty good, it has poison dragon typing along with coverage options in heat wave able to hit almost every steel type that would otherwise take it on. It also gets nasty plot turning it into a deadly sweeper since with 252+ speed it can turn into a speed boosting monster and quickly overwhelm offensive teams quite easily as it has passable bulky to go alongside its offensive stats. It seems to lack draco meteor in its move pool ? Which is a shame rather since dragon pulse isnt particularly a strong move. Scarf sets may be viable as well with modest nature to boost special attack. Really excited to see how this mon works out.
Stakataka is probably not gonna be OU for too long, its defensive typing is horrible and altho it has massive 211 def its hp stat is lackluster with only 61 points and as well as 101 spdef which is not really impressive as it takes around around high thirtys to forty percent from specs tapu lele which a steel type is supposed to check. Even on trick room i doubt it would be a good option either.
Blacephelon is interesting to say the least. Massive spatk and great offensive typing with what im assuming, good move pool as well thanks to fire blast and shadow ball being TMs, perhaps even SUB and CM which to use vs pokemon like chansey as set up bait altho its just speculation. Its speed at 107 seems nice but is rather awkward, getting outsped by the likes of keldeo kartana and lati@s all of which can easily check it due to its horrible defensive stats and arguably just as worse defensive typing. I dont think its signature move has a place on its competitive moveset since it deals recoil damage equal to 50% of its maximum hp limiting it from spamming it and not to mention it is already weak to rocks.
Zeraora is my favorite mons out of all the new mons we have gotten. Its design is sick but looking at a competitive stand point its stats are above average, insane speed, decent attack and decent enough spatk to make use of hidden power ice to lure in the likes of landorus and gliscor since it doesn't seem to have a move to hit them and the latter of which will likely rise in usage thanks to the eligibility of defog with pheal. Super power being able to hit the likes of tyranitar and heatran is also very interesting. Plasma fist is a great physical attack with no draw back unlike most of the commonly available physical electric type attacks which we have very few of to begin with, it also has a secondary effect working like 'Electrify' I assume? which is pretty nifty in certain situation in conjuction with volt absorb allowing it to check tapu koko since it also possesses decent bulk for a fast and offensive mon. Knock off is also never a bad move to have as it gets rid of the targets item which is always nice and progressive in a battle tho im not sure if it will take a place on its standard movesets or not, yet.
For the new tutor moves, despite the hype I dont think defog lando is gonna be the best option, it does defog on the likes of heatran and opposing landorus ( as it can threaten them out with hidden power ice ) i think its a job better done by gliscor since it has reliable recovery and other utility options while lando IMO is better as a rocker than a defogger thanks to its offensive presence. Rotom however i think is a good option since its usage has kinda died down entirely cos it couldnt do the job of really checking common ground types thanks to zmoves and thats not even all of the issues it has. It has volt switch to keep up momentum and hydro pump to take care of common rockers in landorus and heatran while wisp can also cripple mons like ferrothorn and being immune to tspikes and spike is always good, altho a lot of the defoggers have that ability. I dont think i need to talk about gunk shot BB gren as gary explained above, its completely worthless and does not deserve a spot in ash grens moveset at all. Thundurus doesnt seem like a good option as it has severe longevity issues and has to give up a slot on its offensive moveset which i dont think it can afford on the kinds of teams it fits on. Tornadus t might be a good fogger since it has regen to compensate for rocks damage every time and clear them away for next time while also having a great offensive movepool being able to pressure landorus t and heatran and ferrothorn all in one moveset is really nice esp with a good speed stat like it has. Koko seems like a good option for a fast defogger but it doesnt really beat many rockers consistently but interested to see how it will turn out.
I dont think either araquanid or ribombee will have too big of an impact on the meta as both of them lack rocks which webs would really want and struggle to beat Mega Diancie unless you decide to run some random ass hp steel ribombee which then lets scizor defog on you freely, araquanid on the other hand is painfully slow altho its water stabs are strong its still not enough to beat pokemon like mew which it barely misses out the 2hko on and just gets wisp'd and it also doesnt fit the role of an fast lead that a hyper offensive play style such as webs would want.
Im honestly not so excited for USUM outside of the new mons. We have gotten some of the most random move tutor additions which dont make me too happy but im still willing to see how it turns out n_n
