Outlook.com Email Aggregation Platform Developer Needed - Microsoft Graph ingestion system

I am seeking a developer to build a centralized email aggregation platform for a large number of consumer Outlook.com / Hotmail accounts. Project Goal I need a system that allows me to onboard, manage, and monitor thousands of Outlook.com / Hotmail consumer accounts through a central dashboard. Incoming emails from those accounts must be automatically delivered to a single destination mailbox while preserving the original message as received. The destination mailbox may be: Microsoft 365 Gmail Another centralized endpoint if appropriate Required Deliverables The completed platform must: Support thousands of Outlook.com / Hotmail consumer accounts Provide a centralized management dashboard Allow bulk account onboarding Allow account credentials to be imported via CSV or similar bulk-upload method Automatically authenticate and connect accounts with minimal manual intervention Monitor all connected mailboxes continuously Deliver incoming emails to a centralized endpoint Preserve original email headers Preserve original metadata Preserve original envelope information Preserve the original message structure exactly as received Operate automatically without daily manual management Provide visibility into account connection status and failures Performance Requirements Low latency is a critical requirement. The target delivery time is: Less than 10 seconds from the moment an email arrives in the original Outlook mailbox until it is delivered to the destination endpoint. Please indicate whether your proposed solution can consistently achieve this target at scale. Technical Requirements The implementation method is up to the developer. Possible technologies may include: Microsoft Graph API Azure Webhooks Event-driven architectures Custom software Other Microsoft-supported technologies Success Criteria A successful project will demonstrate: Bulk onboarding of Outlook.com accounts. Automated account connection with minimal human intervention. Continuous mailbox monitoring. Delivery of incoming messages to a central mailbox. Preservation of original headers, metadata, and envelope information. End-to-end delivery latency under 10 seconds. Scalability to thousands of accounts. Proposal Requirements Please include: Similar systems you have built. The technology stack you would use. How original email headers, metadata, and envelope information will be preserved. Expected scalability limits. Expected latency. Estimated development timeline. This is a build-and-deliver project. I am not seeking consulting services, workflow reviews, or account-creation analysis. I am seeking a developer who can build and deploy the platform described above. Preference will be given to applicants with direct experience building large-scale Microsoft Graph ingestion systems or multi-tenant mailbox aggregation platforms