Microsoft plans to remove the management of Exchange transport-rule based policies from the classc EAC in mid-2022. Given that Microsoft 365 DLP policies offer the same if not better functionality for Exchange Online and can process other workloads as well, it's a good time to consider transitioning away from the older technology.
Data Loss Prevention (DLP) is a feature of Office 365 E3 and E5 plans. Most DLP policies focus on matching sensitive information types created by Microsoft, like credit card numbers.
How to use PowerShell to disable user overrides for Office 365 data loss prevention policies when the Security & Compliance Center doesn't work.
How to get started with implementing Office 365 data loss prevention (DLP) policies for Exchange Online, SharePoint Online, and OneDrive.