For the Premier League, these are players who may have had face scans held back. This isn't including players who joined the league this summer.
Diego Carlos
Aaron Hickey
Jack Hinshelwood
Adam Wharton
Jarell Quansah
Matheus Nunes
Tyrell Malacia
Danilo
Elliott Anderson
There are also players like Ben White, Martin Odegaard, Lisandro Martinez and Antony who have custom faces but I don't think they can scan Arsenal and United due to their Konami partnership. Sime other players with very dated scans like Jarrod Bowen may have a scan being held back. I expect all of these players to have a face scan coming in a future update along with the newly promoted teams face scans and good craniums for all the players unscanned who joined this summer. Please EA release all the held back scans it's very frustrating for those of us who don't want to wait until March or April to start a career mode.