For the past month or so, cosplayers have been uploading photos to Twitter, asking illustrators to turn their photos into 2D illustrations. Previously, Kotaku published a series of photos that were turned into illustrations. The key difference here is, as mentioned above, cosplayers have been requesting these drawings, using the Twitter hashtag #絵師さんにイラスト化してほしい画像をレイヤーが垂れ流す (loosely translated, that's "Images put out by cosplayers who want artists to illustrate them").
These are not exact reproductions of the photos and are not intended to be, but rather, illustrative interpretations of the cosplay, which are interpretations of the original characters. That makes for a fascinating dynamic, I think.
Here are some standouts: