Models and skins
Two levels of customisation exist. Models are full 3D shape changes that add real hair, tails, ears or held items. Skins are flat textures that wrap over the existing model to swap outfits. Community skin packs bundle dozens of options in a single download.
Custom 3D models
A wide range of community 3D models has been made for the mod. Popular examples include Bunny Girl (black outfit with 3D ears and tail), Aayla Secura (Star Wars Jedi), Emmy (sci-fi robot), Vivian from Zone Zero, FK Halloween (pirate maid), Dorothy (Gothic dress), Nicole Demara, Asa Mitaka, Senko San (fox character), Mitsuri Kanroji, YoRHa 2B, Accurate Christmas, Accurate Jenny, Grok AI and Director Vivian.
These change the actual mesh, not just the texture, so hats, tails and hair sit properly on the character.
Skins
Skins are lighter: a 2D image mapped over the current model to change the outfit. Nova Skin's Minecraft Jenny Mod editor is a common way to create custom skins from a browser and export them for import.
Skin packs bundle many outfits together so a player can rotate through designs without downloading each one on its own.