By default, self developed Metric Templates are stored in the workspace. In an Windows environment these are standardly the paths C:\Users\<user id>\sdb\DatabaseStudio\Database Diagnosis\Default Metric Templates and C:\Users\<user id>\sdb\DatabaseStudio\Database Diagnosis\Local Metric Templates
Database Studio allows to define a distinct folder on your server or network where Database Studio expects to store and retrieve Metric Templates. This folder is meant for being shared with others.
It is recommended to store special predefined Metric Templates in this folder, e.g. Metric Templates delivered by SAP.