The defending champion booked her place in Sunday's final with a 6-3, 6-4 victory in a match which lasted one hour and 45 minutes.
"It's crazy to go to the final back-to-back like this, it doesn't happen very often," said Cornet after the match. "I guess I'm just feeling good and feeling at home in Switzerland. The conditions here with the clay and the altitude, it's helping my game, and I just hope to do the same result as last year.
"It was a very tough match, physically very demanding. It was not easy, with the conditions and the heat, but I'm very happy to be through in two sets, and to be back in the final here in Switzerland."
The No. 3 seed added: "I think it's going to be hard and beautiful at the same time. [Ferro is] the new generation of the French players, and she's such a nice girl. She's a bit like my little sister on the tour, and I like her a lot.
Ferro also secured a straight sets win defeating Pera 6-1, 6-4, and she will compete in the first WTA singles final of her career.