I think it's common to experience this when taking on a significantly different role or being exposed to a new environment in your existing role (such as going to an industry conference for the first time). Your interactions with others are different than what you are used to and our brains are wired to bring that kind of novelty into sharp focus one way or another. It's an errant or exaggerated error signal.
Know that in time it will dissipate naturally as you gain experience and the new interactions become familiar. In the meantime don't let it affect your confidence in your work or others will pick up on that.
1. Consciously acknowledge it as a mental artifact and disregard it as such. Don't just ignore it but call it out in your mind as you feel it happening: "This is just imposter syndrome. I'm going to disregard those thoughts because it's not real and not helpful."
2. Strive for excellence in what you do.
3. Derive and project confidence from following step 2.
Know that in time it will dissipate naturally as you gain experience and the new interactions become familiar. In the meantime don't let it affect your confidence in your work or others will pick up on that.
1. Consciously acknowledge it as a mental artifact and disregard it as such. Don't just ignore it but call it out in your mind as you feel it happening: "This is just imposter syndrome. I'm going to disregard those thoughts because it's not real and not helpful."
2. Strive for excellence in what you do.
3. Derive and project confidence from following step 2.