At this point almost everyone already knows "Steven Universe", which I can now qualify without problems as one of my favorite series (and many). Anyway, this ranking simply consists of discovering which of these cosplay's is the best [No offense to the rest of the cast because they all seemed great].
Garnet / Garnet
Crystal Gem and considered today as the undisputed leader of these. Later it is discovered to be a fusion between Ruby / Ruby and Sapphire / Sapphire.
Sardonice / Sardonyx
Fusion between Garnet / Garnet and Pearl / Pearl.
Sugilite / Sugalite
Unstable fusion between Garnet / Garnet and Amethyst / Amethyst.
Sour Cream / Sour Cream
Biological son of Vidalia and Marty, as well as brother of Onion / Onion.
Sapphire / Sapphire
Sentimental couple of Ruby / Ruby and part of the fusion of Garnet / Garnet.
Protagonist of the series. Son of Rosa Quartz (a gem) and Greg Universe (a human).
Peridot / Peridot
At first enemy and then allied, Peridot / Peridot is a Gem from Homeworld or Natal / Madre Planet responsible for reviewing the Cluster, initially ...
Malachite / Malachite
Fusion between Lapis and Jasper / Jasper.
Pearl / Pearl / Young /
Pearl / Pearl in the moments when he met Greg Universe.
Greg Universe / Young /
Father of Steven Universe in his youth.
Opal / Opal
Fusion between Pearl / Pearl and Amethyst / Amethyst.
Jasper / Jasper
One of the strongest and most perpetual enemies the series has had.
Pearl / Pearl
Crystal gem that has great affection for Steven thanks to the impossible love for his mother, Rose.
Alexandrite / Alexandrite
Fusion between Amethyst / Amethyst, Garnet / Garnet and Pearl / Pearl.
Yellow Diamond / Yellow Diamond
One of the patriarchs of the Mother Planet or Homeworld.
Lapis Lazuli / Lapis Lazuli [CHIKARA COSPLAY]
Gem from Homeworld or Natal / Madre Planet that was initially a terrible opponent to end up becoming one of the protagonist's most powerful allies. [CHIKARA COSPLAY]
Rose Quartz / Rose Quartz / Rose Quartz
Mother of Steven Universe, Couple of Greg Universe and former leader of the Crystal Gems before losing their physical form to have the protagonist.
Blue Diamond / Blue Diamond
One of the patriarchs of the Mother Planet or Homeworld from whom we could finally discover her face.
Vidalia / Young /
Friend of Greg Universe and Amethyst / Amethyst at the time she met the first, as well as biological mother of Nata Agria / Sour Cream and Onion / Onion.
Lars and Sadie
Dependents of the Big Donut who have a complicated relationship.