Nzonzi represented the French national football team 20 times from 2017 to 2020.
The media reports suggest that the Iranian club is going to sign the former Sevilla and Roma defensive midfielder.
Sepahan, headed by Jose Morais, prepares for the 2024-25 Iran Professional League.
The Isfahan-based team, who won the Hazfi Cup in late June, will meet Persepolis as the league holder in Iran’s Super Cup in coming weeks.
Sepahan will host Shabab Al Ahli of the UAE in Isfahan’s Naqsh-e Jahan Stadium in the AFC Champions League Elite Qualification on August 6.