Best setting for rendering video in scenes?

How do you render better videos in cinematic scenes?

I want to create a scene only with videos/media plates. I want to have one foreground character on a green screen and a backdrop video. The reason I want to do this is that I can edit videos through Blueprints and create videos faster than doing repetitive tasks in a normal NLE.

However, when I test render the video, it does not look good. The edges appear jagged, the lighting and colors look strange, and the video feels low resolution, even though I am using 4K assets.

So, what are the things I need to consider to ensure that my video plates in a scene are rendered out in the best possible way? I have a feeling that the pixels are not correctly mapped or anti-aliasing is off.

SOLVED: Upgraded to 5.4 and added Game Overrides to render setting and some Console Variables.

Could you share the Console Variables you used?