Are there any specific questions to identify good leadership skills to ask in the interview?

I have a lot of questions for leadership skills it's a valid questions content me on

" You have a senior staff who's is taking care of everything within the team, such as training new staffs, assisting colleges , managing the floor , handling complaints , completing all tasks before SLA ,etc. His yearly appraisal is a top performer. He's one of the bests! ...For some reason this staff approach you & informed you that he's leaving the company as he's not finding any growth here for so many years & he's tired now. he's doing everything & in return he's not getting any thing from this company except compliments.He found new job already. What can you do to retain this staff due to his value ? "

Leadership .... it is to lead, to pdca, to be empathetic to delegate and deploy, to trust, to focus, to manage conflicts and to be prepared.... l think to evaluate, the conflict management is the trick

"How well do you listen"?

I would recommend you to go with the behavioral type of questions (past experiences) you can pull many themes like the below ones: 

Tell me about a time when you demonstrated leadership skills

Tell me about a time that you took the lead on a difficult project

When have you delegated effectively, describe a time when you led by example

Who have you coached or mentored to achieve success?

Tell me about a time that you led an important meeting

Do you have any business plan ready in your mind in case you are selected? This question will show the pro active approach and management skills of the person which is very important to be a leader.