FC Zurich face a battle to keep hold of prospect Wilfried Gnonto.
The 18 year-old made his Italy debut in yesterday's 1-1 draw with Nations League opponents Germany.
Gnonto was allowed to leave Inter Milan two years ago for the Swiss and is expected to be cashed in this summer.
Sassuolo are keen to bring the attacker back to Italy, though they face competition from across Europe.
SC Freiburg and TSG Hoffenheim are also interested, with Gnonto's deal with FCZ having a year to run.