The player has formally signed his transfer contracts and will remain on loan to Hellas until the end of the current season.
Amrabat has moved this season to Hellas Verona from Belgium Bruges for 3 million euros.
After a conflict between Naples and Fiorentina, Violet settled the deal for 20 million euros to win the services of the 23-year-old.
Soufiane, who is in the middle of the defensive field, participated in 19 games this season in the Italian league and made a single goal.
Amrabat became the fourth Moroccan to play for viola, after defender Manuel da Costa, midfielder Hussein Kharja and striker Mounir El Hamdaoui.
Sufyan is the younger brother of Noordin, who is a member of the current Saudi Al-Nasr wings, who previously wore Watford, Eindhoven, Galata Saray and Malaga shirts.
Fiorentina continues to work on the last day of the transfer market loudly, as it included in the current winter transfers from Patrick Cutroni from Wolverhampton, Igor from Spal, Alfred Duncan from Sassuolo, Christian Kwame from Genoa.