I don't care about winning, but I found that using this line-up in arena ensures me about 85% win rate.

Mei X Chojuro Mei X Chojuro
GNW TenTen x Lightning Main OR X X X
X X X GNW TenTen X Lightning Main


The Talents I use are 2 4 4 1 2 or 2 4 4 2 1 and the summon is eight span bird. GL