You could load the files using the data-import-function from Excel itself:

You can skip the export-sectionof the link below and jump richt to the import-section. Instead of "From Text/CSV" you'd choose "From Workbook".

https://www.customguide.com/excel/how-to-import-data-into-excel

The Power-Query-Editor also allows you to do transformations, joins,... on the data. (Hit "Edit" instead of "Load" after selecting the file) I use the Power-Query-Editor basically daily for hundreds of thousands of datasets and it works pretty well.

If you have the Process set up once you can just open the file, hit "Refresh" at the top and the updated files are reloaded and the transformations are processed.