B-> B+
Hoping to cause some acknowledgement of this little guy, looking at the mons in B+, I think its more then deserving of B+.
I saw widespread use of it while observing people trying to get veil reqs, it was on a squad by Laroxyl that got a lot of use(and it got some SPL use), and this let me observe it interact with the meta. Shellos has several niche's above its competition in mareanie (and frillish to an extent). The main draw is, of course,
Sticky Hold, which lets Shellos retain its eviolite for the entirety of a match, as well as weakening the damage of knock off, letting shellos serve as a switch in to something like vullaby, when another bulky water would not want to lose its item. Shellos has a widespread and customizable movepool, consisting (in order of viability) recover, scald,
clear smog, toxic, as well as surprise factors like
yawn, Counter and mirror coat which can be used to OHKO a timbur after tpunch or something. Acid armor and Amnesia with rest might also be used, I don't see this as a viable option atm though.
Really the best way to showcase Shellos's place in the meta is to look at how it matches up with the best mons in the tier
shellos beats the (imo) best mon in the meta rn, cutiefly, which is not something mareanie can reliably do, losing to QD on the switch with shield dust and roost. Shellos has access to clear smog, which lets it do super effective damage to the bug, pressuring it to roost, but also preventing it from accumulating boosts, and lastly shuts QT down with toxic.
Being not weak to ground attackers, and more importantly, trappers, is super important for a water type and this also lets it be a better check to everything it needs to check, because it cannot be skillessly removed from play. It needs to be at 12/27 health to be killed by a normal roll diglett, and 7/27 health to be killed by trapinch, because trapinch is of course, outsped and needs to kill with first impression.
The crabs are important offensive threats that shellos all but stymies, because it resists their main option, and takes reduced damage for their main secondary attacks, knock off.
Shellos matches up with most sets of the princess of LC much better then mareanie, taking reduced damage from knock off, which denies any attempt at 2HKOing with knock into BB, and has the option of spamming clear smog to insure against any threatening setup variants.
While mareanie and shellos both threaten these with scald, and they both get chunked by tpunch, shellos cannot be beaten 1v1 via being knocked off, and essentially resists both of pawniard's STAB attacks
To be clear I don't think shellos is a better pokemon then mareanie, I just think mareanie is shellos's biggest competition, and I wanted to provide reasons why you might want a shellos on your team, which is what VR rankings is all about :D
I love discussion and I'm not the most experienced in the meta, so if I said anything ignorant or weird, please correct/challenge me. ty for reading my way too long post about this slimy cutie