The former Newcastle United winger joins on a free transfer after leaving RC Lens at the end of last month.
He enjoyed an impressive spell with the French club after arriving in February following the termination of his contract with Mexican side Club America. The attacker scored four goals and provided three assists in 13 appearances.
The winger previously starred in the Premier League with Newcastle United, recording 13 goals and 21 assists in 124 games. He helped the Magpies secure Champions League qualification in 2023 and won the Coupe de France, the first major trophy of his career.
“Maxi is an elite attacking talent who has consistently performed at the highest levels of our sport, including in the Premier League. We’re delighted to bring a player of his quality to Charlotte while he is in the prime of his career,” said General Manager Zoran Krneta.
“His creativity, speed, technical ability and flair make him immediately one of the most exciting players in Major League Soccer.
“Adding a player with his pedigree, experience, and winning mentality will bolster our attacking options and strengthen the team overall. We are excited to welcome he and his family to Charlotte.”