This isn't fanart. This made by who ever does the in-game art. Homura X Asuka confirmed canon. Now we just need Imu X Miyabi, Katsuragi X Hikage and Ikaruga X Yomi for the main ships they tease to be complete.
No it's not; the artist/character designer is Yaegashi Nan, and this is not only a completely different style from what they use, but you can clearly see the signature of an entirely different artist in the actual pic.