Use Monitored Inboxes to view your team’s inboxes in order to track compliance or for training purposes.
Settings for Monitored Inboxes are actually found in Roles and Permissions. You’ll set up Roles that will need monitored inboxes - any inbox that you need to track for compliance or training purposes. When you set up Monitored inboxes, keep in mind that one role must be set up to view inboxes (channels) while the other role is set up to allow monitored access.
Click on your Avatar > Settings > Company Info and Team.

Scroll down to Roles & Permissions.
Select a Role to update. Anyone with this role will have access to Monitored Inboxes. Typically, this would be an Admin role. Click on the pencil icon to edit.

Select the checkbox for Channel Monitoring Admin - Can read access enabled channels.

Click Save.
Now the Admin role will have access to any role that has Channel Monitoring Access enabled.
Edit the role that will be monitored.
Select Channel Monitoring Access - Personal channels are viewable by Admin.

Click Save.