>>53115312It seems pretty common for a Gym Leader to use a type relevant to the location they reside in such as Water-Type gym leaders like Wallace, Marlon and Nessa being on coastal cities, Fire-Type gym leaders like Blaine and Flannery living near volcanoes and Electric-Type gym leaders like Wattson, Volkner & Clemont living near places with energy sources.
I think since a good number of Poison-Types are based around pollution or man-made things and Pokemon's utopic view of humanity's influence on nature makes it pretty uncommon to see a fitting location for those gym leaders at least without a good argument for other types also mainly Bug, Grass, Normal, Dark and Steel Types.
