bubbadork:No, mirror images won't work. That's why my lefty isn't a mirror image. I actually turned him around by aiming backward, then replacing the club with a left handed club because the face, rather than the back, was showing.
Your lefty is hitting cross handed! LMAO! Compare your lefty's hands and location of the glove to a real Lefty, Phil Mickelson.

Your method won't work without a ton of work. WGT has no left handed swing animation from that single setup position.You're method requires regenerating/recreating the swing animations for all 150+ avatars. Mirroring will work with additional artist work on logo avatars and possibly some country avatars.
BTW, there are a significant number of swing animations. It appears each avatar has 36 separate swing animations. Each of the 6 shot types has a different swing and there are 5 forward angles* and one reverse view of the 6 shot types. 36 swing animations X 150 different avatars = 5400 swing animations to be mirrored or recreated.
I know, i know, simple. Write some kind of script to access each animation, pass it to the the existing tool, tell the tool to mirror the animation, rename it and save it in a different directory. That's assuming their development environment supports that. IDK
*turn on the avatar angle option to see the different angles.