Franchi took part in U18 and U20 races in the Alpine Cup until 2017 . At the beginning of the 2017/18 season, Prémanon started in the Alpencup for the first time and finished 30th over 10 km classic. At the Junior World Ski Championships 2017 in Soldier Hollow , she won the silver medal with the relay. In the individual races, she achieved 21st place over 5 km freestyle and 18th place in the skiathlon . In the 2018/19 season she achieved five top ten placements, including second place in the pursuit race in Oberwiesenthal , 13th place in the overall ranking of the Alpine Cup. In the Tour de Ski 2018/19 , which she ended prematurely, she started in the cross-country skiing world cup for the first time and ran in 59th place over 10 km freestyle and 52nd place in the sprint. At the U23 World Ski Championships in Lahti in 2019 , she came in 21st place over 10 km freestyle, 20th place in the 15 km mass start race and 19th place in the sprint. At the Winter Universiade in Krasnoyarsk at the beginning of March 2019 , she took sixth place in the sprint and fourth place in the team sprint, over 5 km classic and in the pursuit. With the relay she won the bronze medal there. In December 2019, she got her first World Cup points with 28th place in the sprint in Davos . At the U23 World Championships 2020 in Oberwiesenthal, she won the bronze medal with the relay. She also took 16th place over 10 km classic, 15th place in the sprint and tenth place in the 15 km mass start race.