I've done an edit of the HBO series into a Hooded Justice origin movie and own the Director's Cut bluray of the Snyder film so I theoretically would have the raw materials. I feel like most fans would love to see this but I'm not sure there's enough footage between the two. I've never been a fan of editing in other media (motion comic or animated) along with live action but that could certainly accomplish it. How did the clips you saw accomplish it?