Suggestions by @beanandbilly

Damson Idris

as Rodolphus Lestrange in Marauders (with British/UK/European Actors)

Eleanor Tomlinson

as Molly Prewett in Marauders (with British/UK/European Actors)

Stephanie Kavumbara

as Young Dorcas Meadows in Marauders (with British/UK/European Actors)

Jackson Brothers

as Young Severus Snape in Marauders (with British/UK/European Actors)

Ashton Dando

as Young Evan Rosier in Marauders (with British/UK/European Actors)

Charlie Bonham-Evans

as Young Evan Rosier in Marauders (with British/UK/European Actors)

Brielle Stoffels

as Young Mary MacDonald in Marauders (with British/UK/European Actors)

Kit Connor

as Young Arthur Weasley in Marauders (with British/UK/European Actors)

Charlie Hodson-Prior

as Young Peter Petigrew in Marauders (with British/UK/European Actors)

Tom Blyth

as Lucius Malfoy in Marauders (with British/UK/European Actors)

Dexter Sol Ansell

as Young Lucius Malfoy in Marauders (with British/UK/European Actors)

Keira Knightley

as Andromeda Black in Marauders (with British/UK/European Actors)

Keira knightly

as Andromeda Black in Marauders (with British/UK/European Actors)

Elodie Blomfield

as Young Andromeda Black in Marauders (with British/UK/European Actors)

Gus Turner

as Young Ted Tonks in Marauders (with British/UK/European Actors)

James McAvoy

as Ted Tonks in Marauders (with British/UK/European Actors)

Jamie Campbell Bower

as Xenophilius Lovegood in Marauders (with British/UK/European Actors)

Elle Fanning

as Pandora Nightly in Marauders (with British/UK/European Actors)

Evie Thompson

as Young Narcissa Black in Marauders (with British/UK/European Actors)

Emma Mackey

as Alice Fortescue in Marauders (with British/UK/European Actors)