The 26-year-old Australian scored the winning goal against Newcastle last weekend after laying on an assist for the Terriers in their opening matchday victory against Crystal Palace.
The newly-promoted club are flying high in second position on the table with with seven points from three matches and Neville believes Mooy will have caught the attention of other clubs after his blistering start to the season.
"He’s been fantastic. Everything that’s been good about Huddersfield, he’s been involved in," Neville said on Premier League Today.
"I think there will be clubs watching him already because I think they’ll be thinking, ‘will he want to progress his career beyond Huddersfield?’
"And he’ll be someone the bigger clubs will looking at to maybe try and buy in January or in the summer."
Mooy joined Huddersfield Town on loan from Manchester City at the start of last season and was an integral part of their run to the Championship playoffs and eventual promotion to the Premier League.
Coach David Wagner decided to outlay a then club-record £10m to make a permanent move for Mooy after he won the the Terriers' player of the year award.
"I think he was a shrewd signing – an important signing in the summer. He’s someone who has bags of talent and fits into the ethos of Huddersfield and David Wagner," Neville said.
"We talked about his delivery. He’s got quality and he can deliver from just about anywhere."