Yes, you can have two Azure Functions running under the same App Service Plan. Azure Functions can be configured to run multiple function apps on the same App Service Plan, allowing you to utilize the same dedicated resources. However, keep in mind that the billing for the App Service Plan is based on the plan itself, not on the number of function apps running within it. Therefore, adding a new function app will not incur additional charges beyond what you are already paying for the App Service Plan.
https://learn.microsoft.com/en-us/azure/azure-functions/dedicated-plan#billing
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