The age old challenge of lefties facing lefties.
Here's a visual search adjustment that hitters describe and is consistent with the concept of directional selectivity ( a neuro/visual concept).
Concept:By changing the direction in which hitters sweep/ get to the left handed pitchers release so that they are not pulling out and away with their sweep leading to a greater chance of " pulling out" with the front side of the swing.
Integrate: Hitters practice a right to left scan to the leftys arm slot in center Toss or bp.
Off the lefty, lefty hitters use a right to left scan path to get to ball flight.
Put another way, lefty hitters will sweep in from the right side of the pitchers arm slot to meet ball flight.
Try it. You have nothing to lose except a diminished batting average facing lefties!
When you ask great hitters the right questions at the right time, you get real answers.