For the first half of the war season, I was placing my 7* Wiccan on defence. However, after moving up a tier, I swapped him out with a 7* ebony maw, with the intention of using him on attack. However, I haven't been able to see him or select him on attack. I'm not sure if this is what is intended with the new placement system or if this is a bug.
Here is him in my roster:

Here is what my selecting attacker screen looks like: