>>37104207>Nidoqueen>Rhydon/Rhyperior>AggronThey're heavily based on Godzilla monsters. Many Daikaiju
most notably, Godzilla himself are commonly shown swimming vast distances. Them and a few others being able to swim despite the Water weakness just highlights how little the type chart actually matters outside of battle in most cases: in addition to the Surfing Rhydon episode, we also see a Tyranitar swimming around to no ill effect at the end of the 4th movie.
>DhelmiseWould be the weirdest of the bunch if it weren't for Gen VII removing the ability to use your own Pokemon to Surf. Since "Using Surf" and "Being able to carry someone across water" have been two entirely distinct talents for as long as Dhelmise has existed, a sapient clump of seaweed that swings around an anchor with enough force to KO Wailord should probably be able to whip up a wave with enough force to use as an attack.
>HariyamaFits into the "fat floats" category with Snorlax and Lickilicky.
>>37104227>ExploudSound waves = sea waves is my guess. This one's pretty close to the Weavile camp of I don't know what's going on.
>SlurpuffDoggie paddle, same as Stoutland or Furfrou
>MewMew is a special case. It's basically a somewhat more limited Smeargle in that learning every move that can be taught was its gimmick up until FRLG fucked everything up. Giving it Surf was a decision made independently of whether or not it could realistically carry someone without Psychic bullshit, it's just to fit with the lore.
>>37104247>RaichuCan only learn Surf from Pikachu, which summons a surfboard from left the fuck nowhere.
>StunfiskUse it as the surfboard lol