Drive boots but isn't "located"
Fixed! Just as it came, it went. There is Paragon NTFS/Disk Utility background to this issue mentioned in a comment above, that might come into play here.
What little I did was figure out there were still Paragon NTFS files in the computer. This is well documented online, the command below should point you to the locations.
sudo rm -rf &quot;/Library/Application Support/Paragon Software/&quot;
sudo rm /Library/LaunchDaemons/com.paragon-software.installer.plist
sudo rm /Library/LaunchDaemons/com.paragon-software.ntfs.loader.plist
sudo rm /Library/LaunchDaemons/com.paragon-software.ntfsd.plist
sudo rm /Library/LaunchAgents/com.paragon-software.ntfs.notification-agent.plist
sudo rm -rf /Library/Filesystems/ufsd_NTFS.fs/
sudo rm -rf /Library/PrivilegedHelperTools/com.paragon-software.installer
sudo rm -rf /Library/Extensions/ufsd_NTFS.kext/
sudo rm -rf /Library/PreferencePanes/ParagonNTFS.prefPane

I then left the computer running overnight copying files with Finder as an emergency preccaution to at least save the files.
Today, I restarted the computer (which I had already done once before without results), and after it took longer than usual to boot, everything was working again.
Guess you can add it to the long history of people having trouble using NTFS on macOS. Tuxera, Paragon, something always comes up sooner or later.

Alternatively, things I was gonna try today. I read someone saying that you can fix the Partition Table by booting to an external macOS drive and adding a new partition to the drive with problems, which &quot;overwrites the partition map&quot; back to normal. I also thought about booting into Safe Mode and seeing if it was recognized there, and physically reconnecting the SATA port of the drive.