1. Here's how

(showing Lumion 12 and newer)

The following technique demonstrates how to create a Camera Keyframe in a second Clip that matches the last Camera Keyframe in the previous Clip. This will make a smooth transition between the two Clips.

The technique can also be used for copying and pasting different Camera Keyframes from one Clip to another.

Make sure to copy the Effect Stack from the source Clip to the destination Clip before following the instructions below:

1.1: In Photo Mode, please make sure that there is an unused Photo Slot in Photo Set 1.
It must be in Photo Set 1 so that the keyboard shortcuts are recognized.

1.2: Make a note of the Photo Slot number. Let's say Photo Slot number 7 in this example.

1.3: In Movie Mode, double-click the Clip that you want to use as the source, and select the last Camera Keyframe in the Clip.

1.4: Then press CTRL + 7 to store the camera angle/position in Photo Slot number 7 in Photo Mode and click on the Save Clip and go back to Movie Mode button.

1.5: Double-click on the Clip that you want to use as the destination and select the first Camera Keyframe in the Clip.

1.6: Press SHIFT + 7 to restore the saved camera position from Photo Slot number 7. The camera position in the 3D view changes accordingly.

1.7: Then click on the Take Photo button to overwrite the existing Camera Keyframe.

1.8: The Clips now have the same ending and beginning Camera Keyframe. Playing the Movie shows no change between the two Clips as wanted.