In the minecraft beta (Not exactly sure if this also applies to regular bedrock), If you stare at an Enderman in Creative Mode, it won't do anything - physical behaviour wise, but it will cause the sound to play. The sound is the stare.mp3 but looped slightly, much louder, and overall more distorted.
Thank you for your report!
We're actually already tracking this issue at MCPE-42977 and MCPE-48248, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main tickets it would be appreciated.
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