Hello.
If you are looking for the extension that supports upload of Excel files without re-formatting and re- saving, there is Store Manage for Magento application.
It handles product import from spreadsheets of CSV, XML, XLS, XSLX, TXT and ODS formats. The solution is paid, but you can download 14-day fully-functional version from the link in my signature to perform the task without fees during that time.
Here is also the tutorial - https://www.mag-manager.com/useful-articles/tipstricks/magento-excel-import-is-not-a-question-any-mo...
