Hi @MSPatrick,
Do you want to create a auto-sync process between Dynamics 365 entity and Excel sheet using PowerApps?
If you want to create a auto-sync process between Dynamics 365 entity and Excel sheet using PowerApps, I afraid that there is no way to achieve your needs in PowerApps currently.
If you would like this feature to be added in PowerApps, please submit an idea to PowerApps Ideas Forum:
https://powerusers.microsoft.com/t5/PowerApps-Ideas/idb-p/PowerAppsIdeas
As an alternative solution, if you want to create a auto-sync process between Dynamics 365 entity and Excel table, I think Microsoft Flow could achieve your needs.
You could consider add a trigger within a flow to detect if a record is added within your Dynamics 365 Entity, if yes, create corresponding record within the pre-defined Excel table (<-- Sync records from D365 Entity to Excel table).
If you want to sync records from Excel table to your Dynamics 365 entity automatically, you could add a Recurrence trigger within a flow, then synx Excel table data into your D365 entity in a specific interval automatically (<-- Sync Excel table data to D365 entity).
More details about Microsoft Flow, please check the following article:
https://docs.microsoft.com/en-us/flow/getting-started
Best regards,
Kris