Hermoso was sold by Real a year ago to Espanyol, where he is impressing this season. The defender has already scored twice this term.
And while his deal carries a €40m buyout clause, Real can re-sign him for €7.5m, says AS.
Real considered Hermoso last summer when Jesus Vallejo's future was up for discussion.
And his form now has kept him on their radar with plans being drawn up to re-sign the defender.