I don't know why everybody is going nuts over Araquanid's offensive capabilities, i mean yeah its very strong, but Crawdaunt is stronger (LO Crabhammer does the same as banded liquidation, and obviously banded crab is much stronger) along with an amazing secondary STAB, priority and swords dance, so if you're looking for a powerful water type wallbreaker then Crawdaunt is your man - not Araquanid.
I think whats really amazing and unique about Araquanid (and most importantly how it stands out from daunt and maybe azu) is it's defensive capabilities. Did you know Araquanid has the SECOND highest base SpD of all bug types? Thats pretty neat. For example as shown in the replay above, nid ALWAYS survives specs psychic from tapu lele from max hp, and it also lives scarf psychic after rocks, making it a decent check to Lele:
252+ SpA Choice Specs Tapu Lele Psychic vs. 248 HP / 8 SpD Araquanid: 283-334 (83.4 - 98.5%) -- guaranteed 2HKO
252+ SpA Tapu Lele Psychic vs. 248 HP / 8 SpD Araquanid: 190-225 (56 - 66.3%) -- guaranteed 2HKO after Stealth Rock
It can actually switch into Pokemon like the landos (yes even lando-i, unless it has rock slide or something), tapu fini, mamoswine, clefable, some magearna variants, even rotom-w to an extent (volt switch only does 35-40% and can't burn you, so either rotom-w stays in and does pitiful damage with pump while you do around 40% back, or they volt switch out and you get to smack whatever comes in - win win), and some others im forgeting. I think this is what sets Araquanid apart from Crawdaunt.
EDIT: On the subject of crawdaunt, i was experimenting with some Crawdaunt calcs and came across this magnificent sight:
+2 252+ Atk Life Orb Adaptability Crawdaunt Knock Off (97.5 BP) vs. 252 HP / 252+ Def Toxapex: 304-359 (100 - 118%) -- guaranteed OHKO
I know this isn't really relevant but holy damn that calc is sexy, seeing Toxapex die in one hit 100% of the time is a beautiful sight no matter what.