Amazon Q Business in ap-southeast-2?

I apologize, but there seems to be some confusion in your statement. Based on the information available in the provided sources, Amazon Q Business is not currently available in the Asia Pacific (Sydney) region (ap-southeast-2).

According to the most recent information, Amazon Q Business is only available in two AWS Regions:

1. US East (N. Virginia) (us-east-1)
2. US West (Oregon) (us-west-2)

The sources do not mention availability of Amazon Q Business in the Sydney region. It's possible you may be confusing this with Amazon Q Developer, which is a different service and is indeed available in more regions, including Asia Pacific (Sydney).

Given the current regional availability, if you need to use Amazon Q Business and your primary region is Sydney, you would need to use one of the two available regions (US East or US West). However, this may have implications for data residency and latency.

Regarding the SSO (Single Sign-On) restriction, the sources don't provide specific information about SSO configurations for Amazon Q Business across regions.

If Amazon Q Business is critical for your use case and you require it in the Sydney region, the best course of action would be to wait for AWS to expand the service's availability to that region. In the meantime, you could consider using one of the currently supported regions if that's feasible for your use case and complies with your data governance policies.

For the most up-to-date and accurate information about regional availability and any potential workarounds, it would be best to contact AWS Support directly or check the official AWS documentation for any recent updates.
Sources
Announcing the general availability of Amazon Q Business and Amazon Q Apps (Preview)
Cross-region inference in Amazon Q Business - Amazon Q Business

Here is error in Console:

Unable to connect to organization instance of IAM Identity CenterSwitch Region Your application must be configured in the same AWS Region as your organization instance of IAM Identity Center before you can assign users and groups. To use Application with your organization instance of IAM Identity Center in Asia Pacific () | ap-southeast-2, choose Switch Region.

Switch Region ends to: