Suggestions by @cameronholmes

Domhnall Gleeson

as Mad-Eye-Moody in The Marauders

Jude Law

as Professor Albus Percival Wolfrick Brian Dumbledore in The Marauders

Cameron Britton

as Rubeus Hagrid in The Marauders

John Boyega

as Kingsley Shacklebolt in The Marauders

Natalie Dormer

as Narcissa Black in The Marauders

Dan Stevens

as Lucius Malfoy in The Marauders

Jane Levy

as Molly Prewitt in The Marauders

Arthur Darvill

as Arthur Weasley in The Marauders

Ben Whishaw

as Frank Longbottom in The Marauders

Carey Mulligan

as Alice Fortescue in The Marauders

Emilia Clarke

as Alice Fortescue in The Marauders

Adam Driver

as Severus Snape in The Marauders

Andrew Garfield

as Remus Lupin in The Marauders

Karen Gillan

as Lily Evans in The Marauders

Ben Barnes

as Sirius Black in The Marauders

Aaron Taylor-Johnson

as James Potter in The Marauders

Sam Riley

as Peter "Pete" Wisdom in Excalibur

Daniel Radcliffe

as Peter "Pete" Wisdom in Excalibur

Zoë Kravitz

as The Beetle in Iron Heart

Sophia Di Martino

as Fafnir in Loki