Jeremie Boga has attracted interest from Atalanta and Napoli, among other European clubs, but the winger's agent is unclear if Chelsea will activate a buy-back clause.
The 23-year-old has impressed in Serie A since joining Sassuolo, including scoring eight goals in the currently suspended 2019-20 campaign.
Boga moved to Italy in 2018 after making just one first-team appearance during his time at Chelsea, having spent time out on loan at Rennes, Granada and Birmingham City.
The Premier League club reportedly has an option to sign the player back, though Boga's brother Daniel - who also serves as his agent - is unaware if a return to Stamford Bridge is likely.
Asked in an interview with Calciomercato.com if Chelsea do not intend to trigger the clause, he replied: "This, at the moment, I can't tell you."
If the Blues decide against a return to England, Boga seemingly has other options on the table - including two of Sassuolo's top-flight rivals in Italy.
Daniel Boga revealed he has held talks with both Napoli and Atalanta - plus "other European clubs" - but there had been no contact yet with AC Milan, despite speculation they want the forward.
"As far as AC Milan is concerned, I haven't had any contact with them yet. I don't know if they are really interested in Jeremie," he said.
"You have to look at what the sporting project will be, but Milan is a great club. It can always be interesting."
Sassuolo have resumed training ahead of a possible return to action in Serie A in June. The league has been suspended since March due to the coronavirus pandemic.