The Argentina-born forward has made just 12 appearances for Inter since joining from Atalanta in January 2013.
Schelotto made his Inter debut in a 3-1 defeat by Siena before scoring his first, and only, goal for the club in a 1-1 draw against city rivals AC Milan in February.
With fierce competition for starting places at Inter, Schelotto has joined Sassuolo with the option to sign half of his ownership at the end of the season.
"Sassuolo had a good behaviour with me and with Inter," the player told Sky Italia.
"I'll undergo medicals. I want to play a great season; it will be different in comparison to Inter. I want to play, this is what I want."
Despite being born in Argentina, Schelotto's ancestry means he is eligible to represent Italy and, in 2011, he featured in the European Under 21 Championship.
Schelotto's lone international cap to date came in 2012 when Cesare Prandelli called the 24-year-old into the senior squad for a friendly against England.