External guest - Ability to comment on reports based on RLS ?

Hello!

I work at an investment company where we have created reports for our subsidiaries.

Our subsidiaries have access to a published PowerBI-app through RLS-security in the underlying dataset, allowing them to see only their own company in the report.

Now to my question. 
I was curious about if there is currently any possibility for these external users to drop comments - directly in the report or on specific visuals, where they can comment on their specific report without creating complete comment-chaos where all external guests are commenting on top of each other and seeing each others' comments all at once. Perhaps there is a better way to explain what I am trying to say, but I hope you see me concern. 

Optimal would be if each external user is able to drop comments on their numbers, without other external users with a different RLS are able to see those comments - while also us as admins can filter out a specific user's comments and see only what he or she is commenting on. 

Maybe what I am asking for is not currently available - I was just curious about what the possibilities are.
Many thanks in advance.