Hi Christoffer,
Unfortunately, in my experience, no, that will not be sufficient--Power BI's scheduled refresh will only be able to access whatever data was loaded to the sheet the last time you actually opened it (which defeats the purpose of a scheduled refresh, in this case). The new sync solution is more or less a Schrödinger's Spreadsheet, where the data only "exists" to other automated services like Power BI and Power Automate if you have opened and viewed the spreadsheet to manually trigger a resync.
If you identify a good solution in Power Automate for opening and refreshing an Excel file, please share on this thread, as I'm sure several of us will find that to be a useful workaround until the above limitation is (hopefully) addressed.
Thanks!