Like Keanu Reeves for the mainline series, Ana de Armas did most of her stunts, including using an actual flamethrower to (safely) burn a man alive on camera. She admitted in interviews that the first time she tested out the weapon, she broke down crying on set at the sight of setting a person on fire.
Norman Reedus was in-between filming seasons one and two of The Walking Dead: Daryl Dixon (2023), so he had to keep the eponymous character's trademark hairstyle.
Eve's back tattoo, "Lux In Tenebris" means "Light in Darkness". It's from John 1:5 which describes how Jesus came to Earth in order to rid the world of sins.