When Evie leaves Ice Block, there's a brief moment where she vulnerable before she can Blink away. Time your Pounce and Daggers to finish Evie off if her HP is low, or for some parting damage if she has the Reprive legendary card.
Just pick something else. Maeve's mobility combined with her Double Jump and small hitbox makes it merely possible to land a shot on her, while she can burst you down in a few nanoseconds. Simply avoid her.
Evie really isn’t supposed to engage with the other Flanks. But in some situations you may have to. You are most likely to win a 1v1 with Maeve by using Evie’s Sbowglobe talent. Maeve at full health will best you at close range.