Systems Manager Inventory support Organization and report?

Yes, AWS Systems Manager Inventory does support AWS Organizations and provides organization-wide visibility.

1. Organization-wide view: Systems Manager Explorer (which works with Inventory data) provides a customizable operations dashboard that reports information about your AWS resources across your entire organization. After completing Integrated Setup within AWS Organizations, you can aggregate data in Explorer by Organizational Unit (OU) or for your entire AWS organization. Systems Manager aggregates this data into the AWS Organization Management account before displaying it in Explorer, giving you a comprehensive view across all accounts.

2. Reporting capabilities: Systems Manager has built-in reporting features through its Inventory, Explorer, and Compliance capabilities that allow you to report on the overall compliance of nodes. For more advanced reporting needs, you can implement automated solutions that leverage AWS services like Lambda, EventBridge, Step Functions, and DynamoDB to consolidate Systems Manager data from multiple accounts, generate comprehensive reports, and distribute them via email and Slack notifications. These solutions can help you track patching operations and maintain visibility across your infrastructure.

It's worth noting that to use Systems Manager features organization-wide, you'll need to integrate it with AWS Organizations. For larger deployments, AWS recommends designating a delegated administrator account rather than using the management account directly for Systems Manager operations.
Sources
AWS Systems Manager and AWS Organizations - AWS Organizations
Automate Systems Manager patching reports via email and Slack notifications in an AWS Organization | AWS Cloud Operations Blog
Org Management account - AWS Prescriptive Guidance