In October, Derwael competed at the World Championships in Stuttgart. During qualifications, she helped Belgium finish in tenth place; while they didn't qualify for the team final, they did qualify as a team for the 2020 Olympics Games in Tokyo. Individually, Derwael qualified for the all-around, uneven bars, and floor exercise finals. During the all-around final, she finished in fifth place but received the highest uneven bars score of the day. During the uneven bars final, Derwael scored 15.233, earning the gold medal and defending her World title on the uneven bars. Derwael became the fifth woman in World Championships history to successfully defend her uneven bars title after Maxi Gnauck (1981, 1983), Daniela Silivaș (1987, 1989), Svetlana Khorkina (1995, 1996, 1997, 1999, 2001), and Fan Yilin (2015, 2017). Afterward, she withdrew from the floor exercise final, citing her previous foot injuries and wishing to remain healthy in the lead up to the Olympics.