Yes, this is a correct way to upload multiple files.
It does not work, because your server does not support preserving file timestamp.
You can make WinSCP not try to preserve the timestamp by adding the -nopreservetime
switch to the put
command.
put -nopreservetime c:\temp\*.xlsx
For more details see the documentation for the error message Upload of file .. was successful, but error occurred while setting the permissions and/or timestamp. If the problem persists, turn off setting permissions or preserving timestamp. Alternatively you can turn on 'Ignore permission errors' option..