Yes, you will need to make a small application to perform it but that would be fine.
1) Set up your metadata columns for the document library.
2) Build an application that iterates through the document library and looks up in the spreadsheet for the file name
3) Add the correct data into the managed metadata columns.
You need to make sure that the account you use has sufficient permissions to do this, you can do this by making it a windows form application in visual studio or a console application, then adding the windows account under the permissions tab as full permissions and as an administrator as full permissions under central admin for the managed metadata service.
However if you are unable to write an application for this, then no it is not OOTB.
Some links for you to get you going:
http://stackoverflow.com/questions/4350812/how-can-you-edit-sharepoint-metadata-from-c
http://stackoverflow.com/questions/6789648/query-excel-sheet-in-c-sharp
I hope this helps.