Changeling

Changelings are shapeshifting beings related to the fey who live in humanoid societies, rarely showing their true forms.

Appearance
In their true form, changelings are extremely pale, showing features devoid of detail, with colorless eyes and silver-white hair.

Personality
Changelings use their shapeshifting abilities as a form of expression, creating complex stories behind the personas they use, or showing their mood through improvised faces they made up in that very moment.

Abilities
As a playable race, changelings have the following abilities:
 * Shapechanger: Using an action they can change their appearance and voice at will, even adapting their size between small and medium. However, they can't assume the abilities of other races, neither take a form without the same basic arrangement of limbs they have.
 * Changeling Instincts: they gain proficiency with two of the following skills: Deception, Insight, Intimidation, Performance, or Persuasion.

As non-playable characters they also gain access to:
 * Unsettling Visage: They can make someone frightened if said creature doesn't succeed on a Wisdom saving throw. Once a changeling uses this ability they can't use it again until they finish a long or short rest.

Note that for those changelings that are fey, instead of humanoids, some spells have no effect on them, since they target humanoids exclusively, while other spells will affect them precisely because of their fey nature.

History
Changelings are not native to Exandria. It is said that they are originally from the Feywild, sharing the mutable essence of that plane, although many of them live in the Material Plane like humanoids. They seem to be related to doppelgangers, monstrosities with very similar abilities, and generally with worse intentions.

When changelings settle in a humanoid society they tend to develop an identity they feel comfortable with, although there are also cases (especially with adventurers) in which they have more than one persona prepared, often suited for different situations, such as negotiations or battles.

Notable changelings

 * An Emonian tavern keeper seen in.
 * Possibly their daughter.
 * Possibly one of Morrighan Ferus' customers at The Maiden's Wish casino, who had shapeshifting abilities.

Trivia

 * In folklore changelings were considered the fey babies left behind in the place of human children stolen by the faeries. Some variants of these legends were more general, considering changelings any substitutes for humans kidnapped by the fey.
 * Changelings were firstly featured as a playable race in Eberron: Rising from the Last War, although the term was also used in the Monster Manual to refer to the doppelganger offspring of a humanoid woman.
 * According to Matthew Mercer, initially he didn't considered changelings as one of the Exandrian races. However, when a poll was organised to choose the gender, race and design for a secondary character in The Legend of Vox Machina, the changeling was one of the options, and was eventually chosen for said character. This made Matt accept it as part of the canon despite its accidental presence in the list of available races in the poll.