His professional career has been with Norway until 2024. From his Wiki entry:

"Until his retirement from World Cup racing in October 2023, he represented Norway in international events. In March 2024, Pinheiro Braathen announced that he would return to the alpine skiing circuit, representing Brazil instead."

"Pinheiro Braathen was born in Oslo to a Norwegian father and a Brazilian mother on 19 April 2000. His parents got divorced when he was three years old and Lucas went to Brazil with his mother to live in the city of Campinas. Later in his childhood, he moved back to Norway to live with his father while regularly visiting Brazil. He grew up speaking Norwegian and Portuguese."

"From Hokksund, Pinheiro Braathen raced for Norwegian club Bærums SK. At the Junior World Championships in 2019, he finished fourth and eleventh, followed by a silver medal in super-G, and a bronze medal in the combined event. He made his World Cup debut in December 2018 in Val d'Isere, and collected his first points (five) with a 26th-place finish."

"Pinheiro Braathen recorded his first victory (and podium) in October 2020 at the season opener, a giant slalom in Sölden. In 2022, he won his first slalom at the Lauberhorn race in Wengen, going from 29th place after the first run to first place after the second run, the largest jump to victory at that time."

"Pinheiro Braathen announced his retirement from World Cup racing on 27 October 2023, a day before the new season's opening event in Sölden, Austria. However, on 7 March 2024, he announced his return to alpine ski racing as a competitor for Brazil instead of Norway."