G Suite provides a feature to create Directory with the details of users in the domain.
You have just have to Enable Contact Sharing option from your Admin Console and you are ready with a directory of all employees with their Email addresses.
Go through the following steps to Enable Contact Sharing.
Step 1: Log in to your Admin Console and go to G Suite.
Step 2: Select Contacts and go to sharing settings.
Step 3: There you can declare settings as needed.
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