I would err on the side of caution with these so-called MongoDB-compatible databases. Most of them (such as Cosmos DB) only really support basic CRUD operations

I would err on the side of caution with these so-called MongoDB-compatible databases. Most of them (such as Cosmos DB) only really support basic CRUD operations and none of MongoDB's advanced indexing and querying capabilities (such as MongoDB's aggregation framework cf. https://www.mongodb.com/presentations/webinar-exploring-aggregation-framework https://www.mongodb.com/presentations/webinar-exploring-aggr...)