Can a Changeling with the Actor feat have permanent advantage on Performance and Deception checks?

Question

The changeling's Shapechanger trait says (E:RftLW, p. 18; WGtE, p. 61):

As an action, you can change your appearance and your voice. You determine the specifics of the changes, including your coloration, hair length, sex, height and weight. You can make yourself appear as a member of another race, though none of your game statistics change. You can’t duplicate the appearance of a creature you’ve never seen, and you must adopt a form that has the same basic arrangement of limbs that you have. Your clothing and equipment aren’t changed by this trait.

So basically, as long as the person you are changing into is/was a real person, you are always passing yourself off as a different person.

The second benefit of the Actor feat says (PHB, p. 165):

• You have advantage on Charisma (Deception) and Charisma (Performance) checks when trying to pass yourself off as a different person.

The way I read it, a changeling would always have advantage on Deception and Performance checks, because they are always trying to pass themselves as a different person. Is my interpretation correct? Or is the meaning of the Actor feat that they only have advantage when they are trying to prove that they are a different person, not in other situations?

I'm really curious whether this is kinda broken, because a bard or rogue with Expertise and advantage on all Deception checks could be a crazy good liar.

Answer 1

No, only on checks related to the identity they've assumed

You already got to that in your question:

Or is the meaning of the Actor feat that they only have advantage when they are trying to prove that they are a different person, not in other situations?

That’s exactly it. Actor gives you advantage on deception and performance checks that you incur from trying to pretend that you’re a different person. It doesn’t apply to other things you happen to be doing while passing yourself off as another person.

This paragraph from the question also isn’t quite correct:

So basically, as long as the person you are changing into is/was a real person, you are always passing yourself off as a different person.

Not necessarily. You’re just changing your appearance to look like that person. But you might not necessarily actually pretend to be that person. Maybe you’re just showing off your shapeshifting ability as a party trick. Also, Actor doesn’t require that you pass yourself off as a different real person at all; It’s perfectly within the bounds of it to try to pretend to be some made up person like a traveling noble or what not, although of course with shapeshifting and incredible acting skills it’ll be quite beneficial to you if you can find a real person to imitate.

I'm really curious whether this is kinda broken, because a bard or rogue with Expertise and advantage on all Deception checks could be a crazy good liar.

I’d also like to address this point: Advantage or not, a Bard or Rogue – especially the Rogue, because of Reliable Talent – with Expertise in Deception are crazy good liars. So good in fact that they’ll rarely ever fail a deception check for anything that isn’t a completely outlandish claim, advantage or not. This isn’t a problem. They built their characters to be good at something, so they get to be good at that thing.

Answer 2

No, only when the Deception or Performance check concerns identity

you have advantage on Deception and Performance checks when trying to pass yourself off as a different person

This part of the Actor feat gives you advantage on Deception or Performance checks when that check relates to you trying to convince someone you are truly the person you are pretending to be. It does not give you advantage on all Deception/Performance checks as long as you have a disguise on; being a good actor does not make you better at lying generically so long as you're in character.

Thus a Changeling with the Actor feat would always be pretending to be someone else, but while they will have advantage when their identity is in question and they are making Deception/Performance checks to convince others of it, they will not have advantage on generic Deception/Performance checks.

Answer 3

Your last paragraph contains the correct conclusion:

the meaning of the Actor feat [is] that they only have advantage when they are trying to prove that they are a different person not in other situations.

The actor feat defines precisely which checks you have advantage on:

Deception and Performance checks when trying to pass yourself off as a different person

Checks concerning any other information besides your true identity would not gain advantage from the actor feat.