Can we set custom labels defined through Microsoft Information Protection on emails via Graph API?

Question

I am working on integrating Microsoft Information Protection (MIP) with an email system. Specifically, I want to know if it's possible to apply custom sensitivity labels, which are defined through MIP, to emails using the Microsoft Graph API.

Here are the key points I need clarification on:

1. Custom Labels: Is it possible to apply custom sensitivity labels (created within MIP) to emails using the Graph API?
2. Graph API Support: Does the Microsoft Graph API have specific endpoints for applying these labels to emails, and if so, how do we authenticate and implement this functionality?
3. Permissions: What kind of permissions (OAuth or otherwise) are required to apply labels to emails via Graph API?
4. Examples: If possible, could you provide a code example or documentation link that demonstrates how to set these custom labels on emails?

This will help me determine if Graph API can be used to apply Microsoft Information Protection labels in our email automation flow.

Note: I have tried with SingleValueExtendedProperties in the Message object, but it is not working.