DeepFaceLab
The leading software for creating deepfakes
... to strengthen their own pipeline with other features without having to write complicated boilerplate code.
DeepFaceLab can achieve results with high fidelity that are indiscernible by mainstream forgery detection approaches. Apart from seamlessly swapping faces, it can also de-age faces, replace the entire head, and even manipulate speech (though this will require some skill in video editing).