With Map power up, the location is kept in the card.plugin_data. Unfortunately there is no variable made available for it. You can get it through API and a bit of code. The way I would do it is to use a report variable to get all the cards, send it an endpoint using HTTP request and have the end point process it and return the info back to you as part of the httpresponse or some other form you need.
I don't know if you can do it in a native way, but I leave you these posts in case they can help you
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