After months of rumored interest in Kushida by WWE, the signing of Kushida was officially announced at a press conference in New York City a few days before WrestleMania 35 in April 2019. Later that day, Kushida appeared in the crowd at NXT TakeOver: New York, making his debut for WWE NXT in the process. The next television tapings for NXT took place on April 10, 2019. At the tapings, Kushida debuted on NXT's weekly television program in a match against Kassius Ohno.
Kushida made his 205 Live debut as Jack Gallagher's tag team partner to defeat Brian Kendrick and Akira Tozawa on the September 10, 2019 episode.
On the January 1, 2020 edition of NXT, the participants for the Dusty Rhodes Tag Team Classic were revealed, with Kushida being announced along with a mystery partner. On January 8, Alex Shelley was announced as Kushida's partner. On January 15, Kushida and Shelley were eliminated in the first round after being defeated by NXT UK's Grizzled Young Veterans (James Drake and Zack Gibson). At NXT TakeOver: 31, Kushida defeated Velveteen Dream. After the match, Kushida ruthlessly attacked Dream. In January 2021, Kushida began to pursue the North American Champion Johnny Gargano, beginning a feud with him. On February 4, it was announced that he would face Gargano for title at NXT TakeOver: Vengeance Day. At the event, Kushida failed to capture the title from Gargano. Following this, Kushida would begin a feud with Pete Dunne and at NXT TakeOver: Stand and Deliver, Kushida would be defeated by Dunne.
On the April 13 episode of NXT, Kushida would defeat Santos Escobar in an open challenge match to win the NXT Cruiserweight Championship, thus marking his first title in WWE career. Kushida would issue an open challenge for his NXT Cruiserweight Title on the April 20 episode of NXT, facing Oney Lorcan; Kushida would go on to win the match. On the May 11 NXT, Kushida successfully defended the championship against Santos Escobar. Kushida would issue another open challenge for his NXT Cruiserweight Title on the June 15 episode of NXT, facing rookie Trey Baxter; after defeating him, Kyle O'Reilly stepped in to challenge Kushida. The next week, Kyle transitioned into a roll-up for the win, leaving Kushida in disbelief. Meanwhile, a hooded figure hit the ring and decimated Kushida, later revealing himself to be Roderick Strong. Kushida would then team with Bobby Fish to defeat Tyler Rust and Hideki Suzuki of the Diamond Mine. Kushida lost the Cruiserweight title to Roderick Strong on September 21 episode of NXT 2.0.
Kushida eventually formed a team with Ikemen Jiro, due to the pair both having issues with The Diamond Mine, deciding on the name Jacket Time. Kushida would return to the ring on the November 5 episode of 205 Live, teaming with Jiro in a losing effort against The Grizzled Young Veterans after a distraction from The Creed Brothers. Jacket Time's feud with The Diamond Mine would culminate in a six-man tag team match after Diamond Mine leader Roderick Strong got involved, along with Odyssey Jones. Jacket Time and Jones would come out on top in the match, before Jacket Time were announced as participants in the 2022 Dusty Rhodes Tag Team Classic. However, Jacket Time were eliminated in the first round by 2021 winners MSK (Nash Carter and Wes Lee), on the January 25 episode of NXT 2.0. On April 18, 2022, Kushida left WWE after his contract expired.