Suggestions by @veroctrl

Freema Agyeman

as Alecto Carrow in Marauders Era - The Lost Generation

George MacKay

as Grant Chapman in Marauders Era - The Lost Generation

Thomas Brodie-Sangster

as Gildenroy Lockhart in Marauders Era - The Lost Generation

Luke Newton

as Caradoc Dearborn in Marauders Era - The Lost Generation

MJ Rodriguez

as Alicia Spinnet in Trios era

Tessa Thompson

as Angelina Johnson in Trios era

Will Poulter

as Marcus Flint in Trios era

Patricia Allison

as Lee Jordan in Trios era

Asa Butterfield

as Oliver Wood in Trios era

Hoyeon

as Cho Chang in Trios era

Nicholas Hoult

as Fred / George Weasley in Trios era

Alexandra Shipp

as Susan Bones in Trios era

Gemma Chan

as Daphne Greengrass in Trios era

Florence Pugh

as Lavender Brown in Trios era

Iman Vellani

as Parvati Patil in Trios era

Ritu Arya

as Parvati Patil in Trios era

Devon Murray

as Seamus Finnigan in Trios era

Alfred Enoch

as Dean Thomas in Trios era

Aiden Gallagher

as Theo Nott in Trios era

Pedro Pascal

as Victor Krum in Trios era