Recent thread on Trapshooters.com with lots of links on the 2nd page and discussion of 'dot' or tape occlusives
https://www.trapshooters.com/threads/cross-eye-dominate-shooter.919056/

2021 DoubleGunBBS thread
https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=600538

Long threads regarding the visual processing challenges most women deal with
https://www.trapshooters.com/threads/female-shooters-using-two-eyes.836675/
https://www.shotgunworld.com/bbs/viewtopic.php?f=2&t=513876&p=4327530

[Linked Image from photos.smugmug.com]

[Linked Image from photos.smugmug.com]

If she is serious about shooting, it would be well worth connecting her with a coach who understands women's visual issues. Phil Kiner is most gracious about sharing his expertise by phone, and a clinic with Nora Ross would be an excellent choice.