From your description, it seems that you want to migrate the Power BI service tenant from one geo-region to another, right?
Based on my research, all gateways associated with Power BI, PowerApps, Flow, and Logic Apps will need to be renewed after the re-mapping has been completed. So we can't migrate on-premise data gateway settings during the time migrate Power BI tenant.
Community Support Team _ Qiuyun Yu
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