They once talked about it a bit in the past(I think it was in 2013)
Eve currently lacks a real theme,being an evil woman isn't something unique.
They once talked about how they might turn her into a vampire(as vlad is a hemomancer) or a succubus(which i would find rather fittingly)
However I guess that she is also getting a kit rework with her VU,because lets be honest,Eves kit is all over the place.
She is supposed to be an assassin,but her Q is more suited for longer fights.
Some abilities synergize well with AP(Q and R) some with AD(E),so regardless what you built,you'll feel like you're not using everything
And her ult is most useful when it is used to engage a battle,which would actually fit more for a tank.