Implants or photoshopped. Gross either way.
Order:
Magneto & Proffesor X (young versions)
Magneto & Professor X (Old Versions)
Iron Man & War Machine
Wolverine & Sabertooth
Captain America & Winter Soldier
Wolverine & X23
Black Widow & Hawkeye
Batman(afflect) & Catwoman
Pretty clear for me, except for maybe Magneto and Xavier. Young Magneto obviously superior especially after the Apocalypse amp that Old Magneto never received. At the same time, Old Xavier leaves his younger self in the dust.