In 1988, he put his career on hold, and moved to New York to further his jazz studies. While there, he took courses with pianist Richie Beirach at Long Island University, and spent his nights hitting the jazz clubs, where he gained valuable on-the-job training playing such luminaries as Kenny Kirkland, Ravi Coltrane, Vincent Herring, and others. During this period, he developed an interest in forward-thinking post-bop and free jazz, as well as an abiding love of hip-hop and rap. Upon returning to Belgium in 1990, Legnini accepted a position as professor of jazz piano at the Royal Conservatory of Brussels. While there, he joined harmonica legend Toots Thielemans' band, and spent the next several years touring heavily. In 1995, he released his third solo album, Rhythm Sphere, featuring saxophonist Joe Lovano, bassist Philippe Aerts, and drummer Felix Simtaine. Also during the '90s, he developed a close collaboration with saxophonist Stefano di Battista and trumpeter Flavio Boltro, with whom he recorded several albums including 1998's Volare, and 1999's Roadrunner.
Over the next several years, Legnini stayed busy, spending much of his time in Paris and racking up studio dates with an array of artists including Paco Sery, Claude Nougaro, Maidi Roth, Didier Lockwood, and more. In 2006, he released his fifth studio album, the '60s soul-jazz-influenced Miss Soul. Around the same time, he was awarded the Gold Django as France's Musician of the Year. A year later, he delivered the funk-flavored Big Boogaloo, followed in 2009 by Trippin'. He then formed his Afro Jazz Beat ensemble and released 2011's acclaimed The Vox, which garnered a Victoires du Jazz nomination for Instrumental Album of the Year.
Legnini returned to a more straight-ahead sound for 2012's aptly titled Ballads, and quickly followed up with another Afro Jazz Beat album, 2013's Sing Twice! Also around this time he played on sessions with Paris Jazz Big Band, Anggun, and Kellylee Evans. In 2017, he delivered the stylistically expansive funk-, soul-, R&B-infused Waxx Up, featuring guest spots from Michelle Willis, Yael Naim, Ibrahim Maalouf, and others. ~ Matt Collar, Rovi