On April 20, 2018, "My Way" was released, which peaked at number 38 on the Romanian Airplay 100 chart. On May 11, 2018, "Slippin", a collaboration with Gashi, was released. On June 8, 2018, she was featured on the song "Into Your Arms" by American rapper Witt Lowry. A month later, "Salt" was sent to SoundCloud. On August 13, 2018, she released "Not Your Barbie Girl" as a promotional single. "Sweet but Psycho" was released on August 17, 2018. The song became Max's commercial breakthrough, reaching number one in more than 22 countries including Germany, Switzerland, Austria, Norway, Sweden, New Zealand, and the United Kingdom, where it stayed at number one for four consecutive weeks. In January 2019, the song reached the top of the Billboard Dance Club Songs chart, and later reached top 10 on the Billboard Hot 100. Max was also featured on the Vice and Jason Derulo song "Make Up" on October 23, 2018, and made an appearance on David Guetta's 2018 album 7 on the track "Let It Be Me".