From Referee Magazine, September 2020
Most softball catchers are right-handed, but it sometimes seems left-handed catchers are more frequent than in the past. The strike zone does not change, but a few tips on the mechanics of working behind a left-handed catcher is helpful.
Watch warmup pitches
Umpires should do this for each half-inning of the first inning regardless of the catcher’s “handedness” but especially for when the catcher is left-handed. You will get a different look of the pitch as their glove is moving in a different direction. For example, an inside pitch to a right-handed batter requires the right-handed catcher to move the glove slightly and probably not affecting your view of the pitch from your slot position. With a left-handed catcher, the glove will be moving a lot more and towards your slot view.
By taking these warmup pitches you will get a feel for how the catcher receives the pitch and will help you to get a look at the plate in relation to where she likes to set up.
Give them room
You may need to give them some extra room with a right-handed bater and a runner on base in order to avoid interfering with this catcher making a play on the runner. You still need to see the pitch and the entire zone, but you may need to set up a half-step back to avoid the interference. You may also need to step back and open up a bit quicker after a pitch to provide her room to work.
Watch the ball, not the glove
Be aware that this catcher will have different glove movements. As mentioned above, on an inside pitch to a right-handed batter, the glove will move more. Do not allow that movement to fool you into thinking a pitch may be too far inside. The same goes for an outside pitch to this batter; the lack of the glove moving should not be the determining factor for calling a ball or strike. Focus on the ball and not the glove and this will help you stay focused and call an accurate zone.
Adjust and communicate
It may take a few pitches to feel comfortable. Adjust your feet and stance if needed to accurately see the pitch. Listen to the catcher if she asks you to move in case you are interfering with her ability to throw the ball. Work and communicate with the catcher, and not against her, and your game will go much smoother. You both have jobs to do and when you work together, it makes I easier on both of you.