Manchester City striker Sergio Aguero could miss the derby against Manchester United, while goalkeeper Joe Hart is a transfer target for Torino.
Southampton have confirmed the signing of attacking midfielder Sofiane Boufal from Lille.
Walcott played on the right wing in Arsenal's 3-1 win at Watford on Saturday, setting up the second goal for Alexis Sanchez.
Liverpool are unlikely to sign Borussia Dortmund youngster Christian Pulisic this transfer window, multiple sources have told ESPN FC.
Hull City have agreed a fee for Derby County midfielder Jeff Hendrick, sources close to the club have told ESPN FC.
The two Manchester clubs go into the game having won all three of their league games this season.