>>18839932>>18839932That is a little bit of a misrepresentation of the region. Gorebyss and Huntail were only obtained by evolving Clamperl found when diving, Azumarill was only found by evolving marill found in the west of the region by surfing, or in grass, Ludicolo was only found by evolving a Lombre found as a Lombre or Lotad on land, Crawdaunt was only found by evolving Corphish found by fishing in some very limited areas.
The pokemon you would find in water routes in Hoenn were mainly Goldeen, Marill and Surskit in ponds like the early route bodies of water and lakes in towns like Petalburg, Chinchou, Clamperl and Relicanth in underwater locations, and Tentacool, Wingull, Pelipper, Wailmer and Wailord on "ocean" routes.
That is it for encounters, you could find a few other evolutionary lines fishing (Sharpedo, Whiscash, Crawdaunt, Gyarados, Luvdisc and Starmie lines are the ones I remember) but the marine life in Hoenn really was NOT diverse, it was 3 evolutionary lines in ponds, 3 in the ocean, and 3 underwater. The pond ones you had to actively seek out surfing even more than you would already to get, the underwater ones are done well (seaweed encounters were kinda cool) and the ocean encounters were completely fucked.
Note that while I am a huge fan of the gen III games, the flaws in them are also something that should be fixed in remakes. I love a lot of things that RSE did but it takes the blindest hoenn fans to refuse to see that the oceanic routes needed more encounter diversity.