You may import global roles from a CSV file.
The format of this CSV file may be determined by first exporting to that format.
Steps
1. Sign in as a user with at least the Security Administrator capability global role assignment.
2. Go to MANAGE > Global Roles in the banner.
3. Click IMPORT.
4. Browse for a file and click OK.
The import action will produce a log and will update and merge, reporting on the number of roles affected.