Deep Fake Project - superimpose two faces into film scene

I'm looking for help creating a deep fake video where two faces are added over the top of two actors in a film

I am looking for something like this: https://www.instagram.com/p/BwPsjqTltHF/

Another effect seen here: https://www.youtube.com/watch?v=1leXXHfaOFw&t=0s

The film is called 'The Persuaders'.

Aim :
. Insert Person A & Person B faces replacing actors faces
. Scene 0,36s (2 actors at the swimming pool)
. Scene 0,42s (2 actors on the boat)
. Scene 0,47s (2 actors together)

E.g. when we see the 2 actors, we have to replace with Person A & Person B faces.