When importing non-baked animation (i.e. not keyed on every frame) onto a camera in sequencer, Unreal adds extra keys to the rotation and scale attributes as if it is baking the rotation and scale animation. This makes it difficult to adjust animation after importing.
Interestingly, the framerate of the extra keys matches the fbx file e.g. if the fbx file is 24fps but the sequence is 30fps, the 'baked' frames Unreal creates will be at 24fps. Checking 'Reduce Keys' when importing animation helps reduce keys as a workaround, but it's not ideal.
This was reported and tested in 4.23.1 (CL-9631420). This was reproduced in 4.22.3 (CL-7053642), 4.24 (CL-9743443), and Main 4.25 (CL-9686140)
Results: Camera animation is imported. Translation and Focal Length animation has imported correctly. Rotation and Scale animation is imported with extra keys added to every frame.
Expected: Imported animation keys should match the animation keys in the fbx file. There shouldn't be extra keys added to the scale and rotation attributes.
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-82263 in the post.