Merseyside Police said Simone Mastrelli, 30, from Rome, had been extradited to the UK after being arrested on a European Arrest Warrant in Italy in connection with the assault outside Anfield on 24 April 2018.
Mr Cox, a 53-year-old father-of-three from Dunboyne in Co Meath, suffered catastrophic head injuries in the attack.
He has been recovering at the National Rehabilitation Hospital in Dún Laoghaire.
A force spokesman said: “Mastrelli was extradited back to England yesterday and has been charged with Section 20 assault and violent disorder.
“He has been remanded in custody to appear at South Sefton Magistrates’ Court this afternoon.”
As part of a fundraising drive for Mr Cox, a team of Liverpool Legends will take on a team of Republic of Ireland Legends at Aviva Stadium on 12 April.