The Reading Chronicle is reporting Chalobah is likely to join the Royals on a season-long loan deal, while an offer for Piazon is also on the table.
Chalobah spent the second half of last season on-loan at the Madejski Stadium, making 20 appearances.
Reading manager Steve Clarke was non-committal when asked about the prospective signings during his weekly press conference.
"I'm not going to talk about players, I never talk about players," Clarke said.
"It's just speculation. I'm not going to talk about every player that gets mentioned in the press."