When you look at the properties of the external hard drive on Mac, it just displays as a RAW file system with 0 bytes for both used and free space, then the drive is inaccessible and unreadable. If you want to recover data from it, you will need third-party data recovery software, and then reformat the drive on Mac to make it usable again.
A drive that is in the RAW state has a corrupted, unknown, or blank file system. It is not specific to Windows; it also appears on macOS with very slight variations in symptoms. To recover data from RAW drive on Mac, you can try iBoysoft Data Recovery for Mac, a professional data recovery software.
iBoysoft Data Recovery for Mac provides a risk-free environment and delivers a high recovery rate. A Finder-like user interface has been added to this Mac data recovery software, which streamlines and simplifies the process of recovering Mac data. It is fully compatible with T2 and Apple Silicon, and supports macOS Sonoma. It scans the external drive you choose and searches for deleted and lost data, allows you to preview the scanned results, and selects the desired items to recover.
After recovering data from the RAW file format external drive on Mac, you can proceed to format the external hard drive on Mac so that you can use it again and it will show correct used space and free space. You can choose to reformat the drive in Disk Utility or with Terminal.