I'm curious about this because the majority of artwork that portrays Zed without his helm depicts him as an albino with a bunch of scars. So I wondered if that was a RIOT sanctioned canon or if it was a fan design folks ran with because the look certainly does not suit his voice over or style. If it is canon, links to the content, please?
The white hair isn't canon, it's just a common fan design. Not really sure why, although I think there is some logic behind it. When it comes to character design, white hair is sometimes used to portray that a character has had highly traumatic or stressful past experiences, which could potentially fit Zed, considering his past with Jhin and the Kinkou.
TLDR; It's not canon.
I'm pretty sure this's because of a Syndra x Zed fan-comic that was released absolute AGES ago. It got a decent chunk of traction, and I forget if it showed Zed's face-- I think it did, though, so that might be the source. I'm not too sure, though, since it's literally been years since I've seen the thing.
Official artwork of an unmasked Zed would be neat, though.
White hair in many animes and books represent raw power in someone it also represent stressful experiences. It could be that Zeds hair turned white when he unlocked the power of the shadows
