Suggestions by @veroctrl

Tom Brittney

as Thorfinn Rowle in The Freckled Era

Score: +1

Abhay Verma

as James Potter in Marauders Era - The Lost Generation

Score: 0

Thomas Brodie-Sangster

as Septimus Weasley in Riddle Era

Score: +1

Robbie Kay

as Ignatius Prewertt in Riddle Era

Score: +1

Daniel Ezra

as Michael Corner in Trios era

Score: 0

Nico Parker

as Pandora Rosier in Marauders Kids

Score: +1

Kaylen Luke 

as Evan Rosier in Marauders Kids

Score: +1

Florence Hunt

as Marlene Mackinnon in Marauders Kids

Score: +1

Alexander Molony

as James Fleamont Potter in Marauders Kids

Score: +1

Joe Locke

as Regulus Black in Marauders Kids

Score: +1

Noah Jupe

as Remus John Lupin in Marauders Kids

Score: +2

Aryan Simhadri

as James Fleamont Potter in Marauders Kids

Score: 0

Alex Tarrant

as James Potter in Marauders Era - The Lost Generation

Score: -1

Eidin Jalali

as Fleamont Potter in Riddle Era

Score: -1

Joe Locke

as Regulus Arcturus Black in Marauders Kids

Score: +1

Alexander James Rodriguez

as Barty Crouch Jr in Marauders Kids

Score: +1

Earl Cave

as Severus Snape in Marauders Kids

Score: +1

Ruby Stokes

as Petunia Evans in Marauders Kids

Score: +3

John Bradley

as Rubeus Hagrid in Marauders Kids

Score: +2