Shiny - They sparkle and have a different color than their species usually has. Different than the Nintendo Canon Shiny Version, Shinies of this group can now be any color! They can not have unusual patterns / markings tho! (as always spots, some stripes, little heart / star marks and similar are totally fine. )
Monotone PKMN - Most skin / fur / scale pattern are 1 color of different hues. Certain features may remain to the original color.
Example: Monotone Pikachu - Blue
Rainbow PKMN - Skin / fur / scale pattern very light colored or white even. It reflects light in rainbow colors! (Inspired by the tcg)*
They can also simply change their colors / part of their colors, if this suits you more
Mutt PKMN - Colors and markings are 100% customized
Tea Cup PKMN - TINY pokémon that are usually not tiny. Tea Cup PKMN are usual small enough to fit in ones hand. Colored like normal PKMN.
Toy PKMN - At least 1 color of skin / fur / scale pattern are totally customized with a pattern. Patterns can not be single colored. There must be a pattern on the pattern xD
Examples:
Dalmatian pattern replace all yellow on a pikachu.
Blue pattern with yellow stars replace all blue parts of a squirtle.
Colorful Polka Dot pattern replace the color of meowth ear skin inside. - You can make them look like these old fashion plushies:
Holo PKMN - Holographic skin, fur, scales - can be entire holographic or just in markings, some parts of the body. Up to you.
*Rainbow PKMN used to be Mutt PKMN before July 1st. 2019. If you happen to have a Rainbow PKMN before this date, you can now call it "Mutt or Shiny PKMN"
None of these have different body types / shapes than their species usuall has!