System Information
Operating system: Windows 10
Graphics card: NVIDIA GeForce GTX 1070

Blender Version
Broken: All Blender versions
Worked: None

Short description of error
When Alembic camera with "focal length animation" is imported into blender - there is no animation for focal lens - it stays same as first frame focal length mm
Same goes for Focus Distance (Depth of Field)

Temporal solution
The solution is to use Side program like Maya:

1. Import alembic with camera into maya;
2. Export camera as FBX from Maya;
3. Import Camera FBX into Blender;
4. Copy Animation of Focal Length and Focus Distance from FBX Camera to Alembic Camera.

A great solution would be if whyle importing Alembics - there would be an option to import it Localized, and also with desired framerate to chose.