When you find any illusions, simply destroy them with Defiance. This makes tracking down the real Ying and killing her much easier, as she will have no escape options, and no healing source.
When an Androxus activates Reversal and you have fired to much already, dodging around makes you a much harder target to hit. Also, if you want to deal damage, and you have an AoE attack ability, aim slightly in front or to the side to hit him.
Barick's Architectonics legendary turrets can not only keep track of Maeve whilst she jumps around, so you can always no where she is just by keeping one eye on the turret, but will never miss her speedy self dealing constant damage to a squishy foe