Is there a sequence for writing a converter?

Question

reverse engineering

There are a lot of files and all different textures, models, shaders, xml, and so on. I can’t understand if there is a sequence by which you can write a program, or is it easier to check with similar samples? Needed to transfer from xbox-a to pc.
2 samples attached 2 samples

Either this is a protection or a problem after swapa double world when replacing big endian with little.