When you need to create your own custom camera calibration export there is a way how to do it.
Adding your own format
First you need to do is to look for the calibration.xml file which you can find in your RealityCaptur…
https://dev.epicgames.com/community/learning/knowledge-base/jPG2/capturing-reality-add-custom-camera-export-information-into-calibration-xml-file