Pokémon Scarlet and Violet means a new batch of Pokémon coming in Gen 9 - and that means new Shiny forms. Unfortunately, the past few games have had a lot of mediocre Shinies. It is possible Game Freak is listening to fan concerns over Shiny forms and can address them in the latest entry in the series, but only time will tell.
Shiny Pokémon were introduced in Pokémon Gold and Silver as rare variants that have different color schemes than the normal versions of each Pokémon species, and they sparkle when sent out to battle. Sword and Shield introduced Square Shiny Pokémon, which have the same alternate palette, but their sparkle effect takes the form of glittering squares. The new colors a Pokémon receives in these forms are generally unpredictable, like Rayquaza turning from green to black. Unfortunately, they're not really an improvement over the algorithm. Many new Shinies feel too similar to their original forms; Toucannon only changes its beak and eyebrows, Rillaboom is slightly hue-shifted, and Cosmog is literally identical to its normal form except for its cheeks. Morpeko’s Hangry Form only slightly changes its purple to a slightly bluer purple, and Urshifu’s line changes nothing except their muzzles.
Some Shiny Pokémon Have Been Changed, But Will Scarlet & Violet's Be Better?
Since the switch to custom Shinies, a handful of Pokémon has received edits to their Shiny forms. These edits all came with the release of Pokémon HOME, and don't quite fix the worst Shiny Pokémon. Combusken was slightly edited to resemble its original design in Pokémon Ruby and Sapphire instead of the even more underwhelming version from the later games. Meanwhile, Castform's additional forms were actually given Shinies after almost 20 years of just using the default palette. But the question remains whether Pokémon Scarlet and Violet will improve Shiny designs or not.
Another annoying decision in the recent games is that players can't obtain most Legendary or Mythical Pokémon's Shiny forms in normal play - they're locked. In the same way that players may reset their game until they get a Shiny starter Pokémon, it was also possible to reset when fighting Legendaries. In the more recent entries, Shiny Legendary Pokémon are generally locked, eventually being distributed later via events. Event Shinies take all the joy out of hunting for a Shiny Pokémon because they’re just handed to players with no fanfare. Community Days in Pokémon GO have the opposite issue in that they make Shinies too common, showing that it’s difficult to get that balance right to make Shinies feel obtainable, but also special.
With the addition of overworld Shinies in Pokémon Scarlet and Violet, Game Freak is hopefully finally acting on concerns regarding Shiny Pokémon. Hunting them might be fairer, but it means nothing if players don’t like the designs enough. Less Shinies like Morpeko and more like Raquaza would be very welcome in Gen 9.
