With the ability to shift face and form, you are an naturally disposed to being an invaluable tool for those seeking to be grifters, spies, or those who wish to deceive. You are skilled at  infiltration and disguise; you rely on your dexterity and charisma to slip in and charm any group of people you work with. Studying your enemy enough to be them has also made you aware of their weakness and tactics.

Restriction: Changeling Only

Only Changeling can truly become Among Us due to their natural ability to transform.

Your DM can lift this restriction to better suit the campaign. The restriction reflects the nature of the Changeling in most settings, but it might not apply to your DM's setting.

Insightful Fighting

At 3rd level, you gain the ability to decipher an opponent’s tactics and develop a counter to them. As a bonus action, you can make a Wisdom (Insight) check against a creature you can see that isn’t incapacitated, contested by the target’s Charisma (Deception) check. If you succeed, you can use your Sneak Attack against that target even if you don’t have advantage on the attack roll, but not if you have disadvantage on it.

This benefit lasts for 1 minute or until you successfully use this feature against a different target.

Master of Intrigue

When you choose this archetype at 3rd level, you gain proficiency with the disguise kit, the forgery kit, and one gaming set of your choice. You also learn two languages of your choice.

Additionally, you can unerringly mimic the speech patterns and accent of a creature that you hear speak for at least 1 minute, enabling you to pass yourself off as a native speaker of a particular land, provided that you know the language.

Infiltration Expertise

Starting at 9th level, you can unfailingly create false identities for yourself. You must spend seven days and 25 gp to establish the history, profession, and affiliations for an identity. You can’t establish an identity that belongs to someone else. For example, you might acquire appropriate clothing, letters of introduction, and official-looking certification to establish yourself as a member of a trading house from a remote city so you can insinuate yourself into the company of other wealthy merchants.

Thereafter, if you adopt the new identity as a disguise, other creatures believe you to be that person until given an obvious reason not to.

Familiar Face

At 13th level, you have mastered your Change Appearance racial trait. Your unique set of skills allows you to portray yourself as a member of another race indistinguishably. 

While transformed, your appearance can alter a creature's disposition to you. You gain advantage or disadvantage on ability checks towards that creature based on their race and alliances.

The advantage and disadvantage per NPC is to your DM's discretion as to fit with their campaign setting.

Rogue in the Ranks

At 13th level, you have mastered your Change Appearance racial trait. Your unique set of skills allows you to portray yourself as an ally to an enemy as long you use Change Appearance while concealed from your enemy.

While transformed, your appearance can alter a creature's disposition to you. You can "join their ranks" as long as you don't betray their trust towards you.

As a caveat, you may be indistinguishable to the enemy from your party depending on whether they see you transform or you set up some form of identification.

Eye for Weakness

At 17th level, you learn to exploit a creature’s weaknesses by carefully studying its tactics and movement. While your Insightful Fighting feature applies to a creature, your Sneak Attack damage against that creature increases by 3d6.