for email :
Both Yes, but there are two diffrent topics.
RLS is about technical security which able filter your data based on current user (in cloud PBI Service and also on-prem Power BI Report Server). But it is not licence right to use report.
In cloud Power BI Pro workspace you will need Pro licence for each people accessing report.
In Power BI Premium per capacity workspace and also in on-premise Power BI Report Server users (consumers) will not need pay for licence.
1. Yes, why not. It will be an Office 365 account with Power BI Pro subscription.
Take a look at the September 2023 Power BI update to learn more.
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