Display DataType Item as Dropdown list in Forms

Hi community,

does somebody knows a way to display the DataType 'Item' like a List dropdown?

I currently modify a change process and want to use a team dropdown instead of the current team item selector. Of course I can define a separate list for my teams and use this one for my dropdown. The selected team from the dropdown could than be used as team_id.

But this would require that my teams are duplicated. I have to maintain teams in the List and the Team ItemType. For teams this still would be ok, but I want to do something similar for Identities. 

Any ideas?