I would like to move App Service 3, which is part of resource group 2, but uses the application 1 service plan for application service plan 2. Is this possible?
Based on my understanding of application service plan 1 in resource group 1 and service plan 2 in resource group , we cannot do this from the azure portal at the moment. According to an official document , we can change the service, which is in the same group of resources and geographical location.
Only valid plans are displayed (in the same resource group and geographic location)
That we could not create an application service plan in the interface of the change service plan, and also reproduce it. In my version, this is not a development problem, and we could inform the ticket on the azure portal.

But we could also create a new application service plan in the same resource group (resource group 1) and geographic , then try to change the service plan, this will be shown in the service plan interface changes.
In my version, it is not recommended that the WebApp application and Service Plan not be in the same resource group.
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