Will the Ralts Diantha gives always have the ability Synchronize?

Question

Says it all

Answer 1

These are all the qualities of the Ralts she trades you.

Yes, the Ralts you get will always have Synchronize according to Bulbapedia's Diantha Page.

Answer 2

Yes, it will. It will also always be modest, as I have reset the game countless times and have always got a modest Ralts with sycronize on both my X and Y version.

source: Experience