Title: Kashimashi: Girl Meets Girl
English title: Girl Meets Girl

Hazumu was a shy boy who enjoyed gardening, collecting herbs, and long walks in the mountains. One day he finally worked up the courage to confess his love to Yasuna, but she rejected him. 

Depressed, he wandered up Mt. Kashimayama, the place where they first met, to reconsider his feelings. After getting lost, he wished upon a shooting star and received a bizarre twist of fate. 

Now he is a she, and she stumbles headfirst back into social life and relationships only to find that the entire landscape has changed!

(Source: Media Blasters)