This is what was written in a "letter to pilots":
Q10) Do I need to undergo an assessment, like ATPL exam and simulator ride?
A10) Yes, all new hires must undergo the pilot recruitment process due to internal regulations
and from 15th of July, also due to EASA Psychological assessment requirements.
We also wish to emphasize that the process is not intended to put you in an uncomfortable
position by any means and will be adjusted to your Wizz Air experience as far as practicable.
You will be informed in due course."