I might do a Gaunt flashback in HBP with a few quick shots from Voldemort: Origins, since the production is of so high-quality. But! And there is a but! If it looks fanedit-y and breaks with the immersion, I can’t use it. It all depends on how I can mix it in.
The immediate thought of the flashback structuring is something like: quick successive shots of Slytherin emblem on door in forest, the Gaunts faces close-ups, Voldemort’s mother in pain, a birth scene, some quick shots of a love potion, and then Dumbledore at the Orphanage and we follow the scene as presented in the film.
It would all have to be packaged like the transitions in HbP (and my GoF edit) with the smoke transitions.
I might also try and deepfake CoS Tom Riddle onto HbP Tom, but this would be problematic due to different facial structures as well as camera angles. An idea could be to crop his face out of shots, or leave his face obscured due to the lack of detail in Dumbledore’s memories (like his face is almost missing).