Recently, Maeve's Midnight was heavily nerfed - it can be countered by Resilience (at the time of making this) and go down to a minimum duration of around 2 seconds. If the option is available to you, buy Resilience - especially if you're her target.
Contrary to what you may see here, setting your rune in the enemy's line of sight can work to your advantage if you have the Inner Strength legendary. The enemy expects you to be weak and on cooldowns when you return to your rune.
Nullify, nullify, nullify. Bait Maeve into the open, then hit her with the good ol' Nullify beam. More often than not, her Nine Lives will still be on cooldown, and someone else is gonna be there to kill her.