Captain America: Manga War!?
As part of the promotions for the Marvel movie Captain America: Civil War, three major shounen manga titles have also revealed their own versions of "civil war," illustrated by the respective manga artists themselves.
By Tokyo Otaku Mode
http://www.rbbtoday.com/article/img/2016/03/24/140898/513631.html
The titles in this collaboration were Fairy Tail, Daiya no A/Ace of Daimond and Nanatsu no Taizai/The Seven Deadly Sins.
In April 2016, the weekly shounen manga publication included the following three amazing illustrations parodying the Captain America: Civil War movie posters for fans to collect!
3 Manga, 3 Posters

http://otakumode.com/news/5704b0272c2211a633353aad/Captain-America-Civil-War-Collaborates-with-Fairy-Tail-and-More!
For Fairy Tail we have Gray versus Natsu.

http://otakumode.com/news/5704b0272c2211a633353aad/Captain-America-Civil-War-Collaborates-with-Fairy-Tail-and-More!
Nanatsu no Taizai/The Seven Deadly Sins presents Meliodas versus Ban.
And Daiya no A/Ace of Daimond offers Sawamura versus Miyuki.
The manga artists expressed that they were happy to participate in this project as they're fans of the Marvel heroes. This is indeed a dream collaboration for fans of both American comics and Japanese manga!