Hey, why not choose NTFS for Mac? NTFS is the main file system for Windows. Developed by Microsoft, NTFS is fully available for its competitor Apple. So, you can't copy to the Toshiba NTFS external hard drive on your Mac.
Since you don't want to reformat your drive to a macOS-compatible file system, your only choice is to use NTFS for Mac. This tool is designed for helping you read and write to NTFS drive on Mac. Simply speaking, it can help you add files to the NTFS drive or edit and delete files on the NTFS drive on your Mac.
I've used iBoysoft NTFS for Mac. It is truly helpful. You don't need to do any complicated steps. Just download and install this app on your Mac, then it will automatically detect and mount your NTFS drive in full read and write mode. After that, you can copy files to your NTFS drive on Mac, delete your unwanted files, or edit some of the documents in the drive.