This is one of those cases where great effects meet a horrific model…
Every time I look at the model, I see a Owl faced humanoid with spaghetti/ribbon hair. All the particles are nice but I just cant with the model.
Hopefully they change it cuz the community doesnt think this is prestige worthy…
Assuming this is a leak, yes? (Since there’s nothing at all on official channels.) Please make that clear in your title and post, if so.
Nope. Not at all.
Skin Spotlights has been a partner with LoL and Riot for a long long time. Im surprised you don’t know this well known YT channel… 
But to what you said, SkinSpotlight has early access to most of the pbe content and stuff.
He’s a affiliate too so Riot allows him to do such as well.
I know all about that channel, actually. But as there’s been no official announcement and the footage is from the PBE, it’s best considered a leak, imo.
The general policy here is (and has always been) that unannounced content needs to be labeled as such. I know we don’t have a Broken Pipe for the League section, but I’m about to fix that.
Idk how to consider what is truely a leak when it comes to LoL.
Since they already have the PBE with unreleased content, I dont really see it as a leak since they upload it themselves.
Though the splash art of True Damage Senna that was unintentionally uploaded seemed like a real leak since they immediately took it down.
Ex: 
Maybe make a new section in the broken pipe for LoL leaks if u feel so?