The 25-year-old is regarded as one of the best playmakers in European football, but has been troubled by the off-pitch concerns in recent seasons.
However, his representative Marcelo Simonian has suggested that interest is rife in the Argentine midfielder.
"I can only tell you that we are already talking with several clubs in relation to the next window," he told NapoliCalcioLive.com.
"In the next few days I will be travelling to present all the options to Valencia."
Banega has been with Valencia since joining from Boca Juniors in 2008.