How to keep crop operation on replaced image?

Dear all,

I have two images showing the same object in different moments. What I want to do is to crop all pictures to the same area.

My idea was:

  1. insert first picture
  2. crop it
  3. copy and move
  4. replace it with second picture

At this point, I get a picture with the same size of the original one but not cropped.

I am using Libreoffice 5.2.7.2 on Debian, I am sure this behavior was different with elder version on Fedora.

Thank you for your help