Trying to get myself back into drawing since it's been way too long between work, lack of time/energy and art blocks. So as a warmup I felt like trying something simplistic and Sugimori-esque. Can't quite nail his style (especially lineart-ways), but there you have it. I wanted to get these designs out of my head!
So these guys are a regional variant of Shellos and Gastrodon - not sure from which region, they don't quite fit in either Miato or Syona. Like their Sinnoh counterparts, Both versions of Shellos are pure Water-types. Unlike their Sinnoh counterparts, their different appearances aren't just aesthetic - as they affect their types, stats and abilities upon evolution to Gastrodon.
East Sea Shellos peacefully graze on algae, with time incorporating their chloroplasts into their body structure, becoming Water/Grass types and gaining the Regenerator ability upon evolution. They are somewhat slower and more passive than their counterparts, but have a fairly annoying knack for tanking hits and dishing out damage while recovering. They are based on the Elysia chlorotica sea slug.
The West Sea Shellos, however, pursue a more active sort of prey - Tentacool and Tentacruel. As they grow and evolve, they take their prey's most powerful stinging cells and wield them themselves as offensive and defensive weapons, becoming Water/Poison types and gaining the Intimidate ability upon evolution. Slightly faster and more active than their counterparts, they are less tanky, but are equipped with a wider variety of moves that are meant to cripple and sap their foes' strength. They are based on sea slugs in the family Glaucidae, particularly Glaucus atlanticus and Glaucus marginatus.