Hi @Nitin ,
As per the conversation with internal team, the feature to support MongoDB Atlas as sink is under development, and will be released soon (Note: Tentative ETA - in a month).
Once the feature is out, you will receive a notification in Release notes/Updates section of ADF UI.
I would recommend you to please subscribe to Azure updates for new features/release updates on Azure products.
Hope this info helps.
----------
Please don’t forget to Accept Answer
and Up-Vote
wherever the information provided helps you, this can be beneficial to other community members.