Green was recently granted his release from the Argos after three seasons. Upon signing with the XFL, he will enter the league's waiver system and will be acquired by a team at the top of the wire, according to Scianitti.
The 34-year-old built a strong resume in the Canadian Football League. He ranks 15th all time in receiving yards (10,222), 12th in catches (716), and won three Grey Cups.
He was named a CFL All-Star twice and an East Division All-Star eight times.
Green spent the first 10 years of his career with the Montreal Alouettes before he was traded to Toronto in 2017.
The XFL kicked off this past weekend. Among the teams with 0-1 records are the Tampa Bay Vipers, Seattle Dragons, Dallas Renegades, and Los Angeles Wildcats.