In Survival mode on Bedrock Edition, all creepers are appearing with a static blue aura that resembles the charged creeper effect. However, the aura does not animate and instead moves with the creeper’s body, behaving like part of its texture or skin. When the creepers explode, there are no increased explosion in size, no mob heads drop when killed by the supposed charged creeper, they behave like normal creepers in every way except visually.
This seems to be a rendering bug. Reloading the world doesn’t seem to do much and the creepers still have the same visual effects a charged one.
This issue is being tracked at MCPE-217361.