BuddyPress Friendship Restrictions
BuddyPress Friendship Restrictions plugin allows you to restrict BuddyPress Friendship features. You can limit who can add a friend, who can be added as a friend, how many requests are allowed, and how many friends are allowed on your BuddyPress site.
It gives absolute control to the site admins to control how the friends feature works.
Restrict users who can send friendship request by roles
Restrict users who can be added as a friend based on roles.
Throttle BuddyPress friendship request(How many requests can be sent in a specified duration)
Limit the maximum allowed number of friends
Easily extend via filters.
Also, In the future, the plugin will allow setting limits for individual roles.