accent sponge

Someone automatically speaking with an accent when they hear it, absorbing it like a sponge.

Aria: since when does Johnny have a Brummie accent?
Leah: He doesn't, he's just an accent sponge.

infotchat

In Twitch, when someone in the tchat delivers a false infirmation, making the streamer and other viewers believe him until someone debunks him.

Antoine: Someone said in the tchat that you can play phasmophobia with 8 players.
Romain: What? NO, that's an infotchat