The Brazilian will link up with fellow Wolves loanee Connor Ronan, who made the move earlier in the summer.
The 26-year-old played his part in Wolves’ promotion to the Premier League in 2018, scoring 12 goals as Nuno Espirito Santo’s side lifted the Championship title.
However, Bonatini has rarely featured since and spent time out on loan at Nottingham Forest and Vitoria Guimaraes.
Now, his next challenge comes with Grasshopper Club Zurich, who finished third in last season’s Swiss Challenge League.
All at Wolves would like to wish Leo the best of luck while out on loan.