Using this add-on, you can edit any user from ACP, and simply using a checkbox mark the user as Verified.
You can also let users ask for a verification badge and manage their requests.
Verified users will have a badge next to their username (left OR right, based on your choice in the add-on's options) all around the site (even in 3rd party add-ons' pages)
Options
Location of the Badge (left OR right)
Maximum item attachment file size (KB)
Maximum attachments per request
Allowed request attachment file extensions
Requests Per Page
Style Properties
Badge
User Criteria
User requested verification badge at least x times
User requested verification badge no more than x times
Permissions
Manage Verification Badge Requests
Request Verification Badge
Max Verification Badge Request per user
Upload attachments to Verification Badge Request
View own Verification Badge Request
Edit own Requests
Request Verification Badge System
Users will see an option to ask for verification badge, in their profile
Each user can ask for verification badge x times (user group permission)
Users can write a comment and attach files while requesting verification badge
Moderators can reject, accept, or close the requests (approving a request will automatically close all other requests by that user if the user had permission to submit more than 1 request)
The accepted request will mark the user as verified and the user will get verification badge automatically
Rejected requests will lose their verification badge (in the case when another moderator manually granted them the badge while you were checking their request)
Usergroup permissions are added to fully control this feature (permission to request, number of requests, attach files to request, edit request, and manage requests)
Ability to control the number of times each user can request the badge
2 User Criteria (User requested at least x times, user-requested no more than x times)
User alerts for request status change
User's account info/details in request page ("Verification Badge Requests Count" will also show user's all requests)