Choosing a region and zone You choose which region or zone hosts your resources, which controls where your data is stored and used. Choosing a region and zone is important for several reasons:
Handling failures
Distribute your resources across multiple zones and regions to tolerate outages. Google designs zones to be independent from each other: a zone usually has power, cooling, networking, and control planes that are isolated from other zones, and most single failure events will affect only a single zone. Thus, if a zone becomes unavailable, you can transfer traffic to another zone in the same region to keep your services running. Similarly, if a region experiences any disturbances, you should have backup services running in a different region. For more information about distributing your resources and designing a robust system, see Designing Robust Systems. Decreased network latency To decrease network latency, you might want to choose a region or zone that is close to your point of service. https://cloud.google.com/compute/docs/regions- zones#choosing_a_region_and_zone

https://cloud.google.com/appengine/docs/flexible/managing-projects-apps-billing#:~:text=Each%20Cloud%
20project%20can%20contain%20only%20a%20single%20App%20Engine%20application%2C%20and%
20once%20created%20you%20cannot%20change%20the%20location%20of%20your%20App%20Engine%
20application.
Two App engine can't be running on the same project: you can check this easy diagram for more info:
https://cloud.google.com/appengine/docs/standard/an-overview-of-app-engine#components_of_an_application And you can't change location after setting it for your app Engine. https://cloud.google.com/appengine/docs
/standard/locations
App Engine is regional and you cannot change an apps region after you set it. Therefore, the only way to have an app run in another region is by creating a new project and targeting the app engine to run in the required region (asia-northeast1 in our case).
Ref: https://cloud.google.com/appengine/docs/locations

Keywords, Financial data (large data) used globally, data stored and queried using relational structure (SQL), clients should get exact identical copies(Strong Consistency), Multiple region, low latency to end user, select storage option to minimize latency.

Cloud Debugger helps inspect the state of an application, at any code location, without stopping or slowing down the running app // https://cloud.google.com/debugger/docs