Everton tempted the French left-back from Marseille to Goodison Park last summer, but he struggled to find favour under Carlo Ancelotti.
He remains down the defensive pecking order under Rafael Benitez and Standard Liege want to secure his services, according to Belgian daily Het Belang van Limburg.
They are looking to agree a loan deal, but it is unclear whether the Belgian side want it to include a purchase option.
The 20-year-old turned out for Everton against Huddersfield Town in the EFL Cup earlier this month, clocking 75 minutes.
He may struggle for regular minutes if he remains at Everton beyond the closure of the transfer window however.
Standard Liege have so far picked up ten points from five games in the Belgian top flight to sit in fourth place.
It remains to be seen if Standard Liege will be able to get a deal for Nkounkou over the line before the window shuts.
