The Azure Cosmos DB Emulator provides a local environment that emulates the Azure Cosmos DB service for development purposes. Using the Azure Cosmos DB Emulator, you can develop and test your application locally, without creating an Azure subscription or incurring any costs. When you're satisfied with how your application is working in the Azure Cosmos DB Emulator, you can switch to using an Azure Cosmos account in the cloud.
Good News! Azure Cosmos DB Emulator has been added to the catalog as of yesterday - https://patchmypc.com/patch-my-pc-catalog-update-04-06-23