Proof

Blake traced
https://medibang.com/picture/if1807022214530930004084898/

Weiss traced
https://medibang.com/picture/sh1807022105467380004084898/

Ruby traced
https://medibang.com/picture/jw1807020337223310004084898/

Team Rwby Original
http://breica-artwork.tumblr.com/post/105959478066/put-team-rwby-together

All of these were drawn by Breica not them they traced over theirs

Weiss traced
https://medibang.com/picture/fj1807052304189400004084898/

They traced another artist

Weiss Original
https://game-mush.tumblr.com/post/171311368227/ｒｗｂｙのワイス-weiss-schnee-from-rwby

Yang traced
https://medibang.com/picture/gy1806260646053970004084898/

Yang manga original
https://mobile.twitter.com/vizmedia/status/958067391166140416

They traced a scene from the manga

Weiss traced
https://medibang.com/picture/le1806242217495320004084898/

They traced the chapter cover

Weiss manga chapter 4 cover original
https://rwby.fandom.com/wiki/Chapter_4_(2015_manga)

Ruby traced
https://medibang.com/picture/5v1806242007410220004084898/

They traced the cover to the Ruby rose one too

Ruby manga cover original
http://mywongaplc.com/manga/rwby/2/1

The tracer: https://medibang.com/author/4084898/