During 2016, CLC began undergoing a transformation, mostly due to the addition of two new members: Elkie Chong and Kwon Eun-bin.
CLC’s third EP, Refresh, and it’s lead single, High Heels, were released on February 29, 2016. This comeback marked the first appearances of Elkie and Eun-bin. The latter’s addition became controversial due to her double role as a participant of Mnet’s girl-group survival show Produce 101 at the time.
Cube Entertainment then stated that Eun-bin had been part of the group’s original lineup, but was dropped following delays in the production of the group’s debut album. Due to Produce 101’s contractual restrictions, Eun-bin was not able to promote the single High Heels on music shows or other broadcasts, nor appear in the single’s music video.
The agency planned for Eun-bin to join promotions in the event that she was eliminated from the show, or else to postpone her activities as part of the group until after Produce 101 promotions if she was a winner. On February 29, a short version of the High Heels music video that included Elkie, but omitted Eun-bin, was released. The full version of the music video, including Eun-bin, was released on March 21.
In the same year, CLC also made their Japanese debut on April 13, with the release of their first Japanese EP, High Heels. The album includes the Japanese versions of Pepe, First Love, Like, High Heels, and a cover of Kylie Minogue’s I Should Be So Lucky.
On May 12, CLC launched their official Naver V App channel, followed by a broadcast of Eun-bin’s first live appearance with the group. The group then went into a more funky look with the release of their fourth Korean EP, Nu.Clear, on May 30, with the title track No Oh Oh, written by Shinsadong Tiger. They carried out album promotions as a seven-member group in June.
On July 27, they released their second Japanese EP, Chamisma. The EP peaked at #9 on the Oricon Daily Albums Chart, making it their first release to enter the Top 10 of the Oricon chart.
On January 9, CLC held their first solo Japan fan meeting at Tower Records in Tokyo. Eight days later, the group released their fifth Korean EP, Crystyle. It marked a revamped image for the group, with a more charismatic, hip-hop concept. The EP contains six tracks including the EDM/trap lead single Hobgoblin (도깨비), which was co-written by Seo Jae-woo, Big Sancho, Son Yeong-jin, and HyunA.
Crystyle debuted on Billboard’s World Albums chart at #6, while Hobgoblin peaked at #4 on the World Digital Song Sales chart. On May 27, the group held the first fan-meeting for their fan-club, Cheshire, 2017 Cheshire Entrance Ceremony. It took place in the Olympic Hall Muse Live in Seoul.
Seven months later, CLC released their sixth EP, Free’sm, on August 3. The album title is a mashup of the words “prism” and “free”, which describes the group’s musical and conceptual direction for this EP. The album is inspired by the 1990s girl-groups Fin.K.L and S.E.S. It consists of six tracks, including the R&B ballad lead single Where Are You? (어디야?). This was another new image for the group, contrasting with the group’s previous concept in “Hobgoblin”.