There are several unique solutions for this. One of my favourites is DISC team facilitation. We have everyone complete a short behavioural questionnaire, and then I debrief the team together, looking at everyone's different profiles and discussing what motivates each person differently, what strengths they bring to the table, and how the team can work together more effectively overall.
With that said, I've also had a lot of success with simply asking people individually what motivates them.
Hope that helps! Feel free to reach out for a call in follow up!