On April 17, Asuka was drafted to SmackDown as part of the 2018 WWE Superstar Shake-up, making her first appearance by saving Charlotte Flair and Becky Lynch from an attack by The IIconics (Billie Kay and Peyton Royce) and then—SmackDown Women's Champion Carmella. On the May 15 episode of "SmackDown", SmackDown general manager Paige interrupted Carmella, to announce that she would be defending the SmackDown Women's Championship against Asuka at Money in the Bank. At the event on June 17, Asuka lost to Carmella after an interference from the returning James Ellsworth, suffering her first official pinfall loss in WWE. Paige then granted Asuka a rematch that took place on July 15 at Extreme Rules, which Asuka lost after another distraction from Ellsworth, who was hanging above the ring in a shark cage, which Carmella used to win the match. In September, Asuka helped Naomi, who after defeating Peyton Royce was attacked by The IIconics. This led to a tag team match between the two teams on October 6 at WWE Super Show-Down, where Asuka and Naomi were defeated. Also during that time, it was announced that Asuka and The Miz would take part in the upcoming season two of Mixed Match Challenge. They would last until the semi-finals, where they were eliminated by eventual winners R-Truth and Carmella. On November 18, Asuka took part in the Survivor Series as part of Team Smackdown, where she was the last woman eliminated from Team SmackDown.