Thank you!
I understand you explanation, but I don´t know how to do step 3: Connecting both datasets inside the PROPERTY-PANEL to the same database, on both of your sites.
Maybe I did not explain correctly. Two pages are two different websites, two different domains. I have “News” database and connected dataset for that database and repeater that shows content. I want to add repeater on other website (other domain) that shows same news from original database.