I want to change the sort order of agents for each group

In our operation, the same agent belongs to multiple groups, so
The number of people in the group is a little large, but each group  has a main person in charge.
I want to display the main person in charge at the top.
(It is possible to search by entering a person's name in the search, but I hope to reduce the effort as much as possible.)

Specifically, for example, A , B , C , and D belong to group 1 and group 2 at the same time.
The display order of group 1 and 2 is all A , B , C , D,
I want to set the order of  Group 2 for just lick D , C , B ,  A or D, A , C, B.