The Brazil international has played just 23 minutes of Premier League action so far this season with his only two starts of the campaign coming in the Carabao Cup.
The 19-year-old is rumoured to have voiced his concern to his representatives despite Alonso's preseason comments over his 'youth and potential' guaranteeing him a role in 2026/27.
Barcelona are now rumoured to considering a January loan offer if Hansi Flick needs extra bodies in attack.
Ferran Torres and Robert Lewandowski were replaced by Anthony Gordon and Karim Adeyemi over the summer, but Flick failed to land Julian Alvarez, and that situation will not be revisited mid-season.
Estevao could provide a short term squad addition with Chelsea open minded over his long-term place at the club.