Can the solution manage budgets allocated at the application and resource group and/or subscription level? Can budgets be set by cloud consumption groups with time limits for usage?

Budget threshold management and alerts:

Yes, Exivity supports managing budgets for applications, resource groups and subscriptions as well as other business objects for a specific time period. 

Users can configure mail, slack or webhook notifications when a certain percentage threshold is hit. 

Exivity is an API first solution meaning you can do any CRUD operation against the API of Exivity. This makes it easy to integrate with in-house tools.