bbPress Contacts is a WordPress plugin by Samuel Elh that allows you to add contact and bookmarking customizable buttons (add contact/remove contact) to bbPress profiles, and in the forums below topics and replies author details.
logged in members to add this user as contact or remove them as contact.
A contacts section is added to the bbPress profile of current user, allowing them to:
View bookmarked users and contacts
Search these users
Quick removing a contact with a small cross button
Paginating through these results.
Also, AJAX can be enabled (enabled by default) to process buttons faster, and process the search, pagination and list the available contacts in the bbPress profile page.
More info: https://wordpress.org/plugins/bbp-contacts/