Developed scoped applications cannot be edited in all the instances unless they are moved through update sets. Moving the scoped applications through update sets is not a recommended approach by Service Now.
Scoped applications should be developed in an instance and moved to application repository. Once the scoped application is fully developed then it can be installed from the application repository. Scoped applications should never be installed through update sets. There should only be one instance in development mode for that specific scoped application.
Customers often develop a scoped application in an instance and move via update set to another instance thus compromising the security of the scoped application. This way the scoped application can be edited in another instance as well which is not a best practice.
The installed applications are in Store applications (sys_store_app) whereas the developed applications are in Custom Applications(sys_app) table.