One flag is a translation image of the other.
This is as one of the flags is a duplicate of the other which is moved up / down by a certain distance based on which flag you are basing it on.
For example, if you are looking at the top flag. It appears as if that flag was duplicated and pulled down to show the bottom flag. Therefore, one flag is a translation image of the other.
It isn't that one flag is a rotation image of the other as both flags are vertical and aren't rotated in any direction. Therefore, it isn't that one flag is a rotation image of the other.