How to synchronize two MongoDB databases?

Question

MongoDB

There are two databases with the same data, but different indexes and sharding. One is optimized for processing, the other for reading.
Is there a way to set up automatic database synchronization?
As I understand mongodb 4 does not support master-slave replication. Now I have a script that uses cron to transfer data from one database to another. Is it possible to do this with some standard MongoDB tools or a third-party tool?

Answer 1

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};