Hi ,
At this time, there isn't an easy way to import those cameras and images into Twinmotion, and you would have to do them manually.
The Datasmith team is looking into adding the option to allow Datasmith to export and import camera data from design programs, which would simplify the image creation process and allow Twinmotion to automatically import those cameras as images. If you have any feedback on particular aspects of this feature you would like to see, you can submit it on the roadmap item for the feature here, so the developers can consider implementing your feedback.
Best,
Raghib