Field level security - field specfic security roles

Hello,

A user (B) in a branch business unit can normally access his own business unit contacts but not contacts in other business unites.

A user  (A) in the HQ  business unit can access all contacts in the organization.

I would like to enable user B to read all contact names, so he could see that a name exists but he wouldn't be able to know anything about that contact since all other fields are hidden entirely or the content is starred (***).

Is it possible with a combination of team security roles, user security roles and field level security to achieve field-level security roles?

How?

I would like to achieve it to enable duplicate detection rules take effect on organization level.