2021–2024: Unnatural, The Black, competition show, and Chinese members departure
WJSN released their ninth extended play Unnatural, with the title track of the same name on March 31, 2021. On April 26, WJSN announced the formation of their second sub-unit WJSN The Black, featuring members Seola, Exy, Bona and Eunseo, along with announcing their first single album My Attitude and its title track "Easy", which was released on May 12. On September 23, WJSN released the promotional single "Let Me In" through Universe Music for the mobile application Universe.
On January 5, 2022, WJSN Chocome released their second single album Super Yuppers!. On February 21, 2022, it was confirmed that WJSN will be participating in the second season of Mnet competition show Queendom, which ran from March to June 2022. Dawon did not participate in the show, while Bona joined in the third round due to scheduling conflicts with her drama Twenty-Five Twenty-One. WJSN was announced as the winners of Queendom 2 at its live finale on June 2. On May 6, Starship Entertainment announced the group's would be holding their fourth concert tour, titled '2022 WJSN Concert Wonderland' at the Olympic Hall on June 11 and 12. Following their win on Queendom 2, it was announced that WJSN would be making a comeback on July 5 with their special single album Sequence, with the title track "Last Sequence". On November 18, Starship Entertainment announced a fan concert '2023 WJSN Fan-Con Codename: Ujung' that took place on January 7 and 8, 2023.
On March 3, 2023, Starship Entertainment announced that Xuanyi, Cheng Xiao, and Meiqi had departed from WJSN following the expiration of their contracts. In the same announcement, it was also announced that Luda and Dawon chose not to renew their contracts, but did not specify whether they would remain in the group, while the rest of the members renewed their contracts with the company. On March 13, 2023, Soobin clarified that Luda and Dawon have not left WJSN, followed by an official statement by Starship Entertainment backing up the information.
In a 2024 interview with South Korean news outlet Newsen, Yeonjung revealed that there "aren't any concrete plans" for a group comeback.
