In some ways FCP media management is more sophisticated than any other NLE -- provided your media and library are on APFS or Mac OS Extended Journaled (HFS+) volumes. Do not use ExFAT or any other volume type.
If your media and library are on APFS or HFS+ volumes, you can shut down FCP, rename every media file, then move every media file to a different folder on that volume, then launch FCP and it will find all the files without relinking.
When using external media, the only thing inside the library are "symlink" pointers to the media files. If your media and library are on APFS or HFS+ volumes, you can shut down FCP, go inside the library and use Finder to *delete* all symlinks. Upon launching FCP it will transparently rebuild all symlinks and all files will be on line. These are just extreme examples of how well FCP media management works. To my knowledge, no other NLE can do this.
The above is possible because FCP resolves addresses to files by pathname and by inode. Inode is a Unix-type auxiliary lookup system, but it only works within a given volume. If you move files to another volume, then relink is necessary.
For that reason (and for general management purposes) it's best if all media files have a unique name. You don't want cases where multiple Sony video files have the name c0001.mp4. That will work provided you never move a file to a different volume and don't relink them. However it is problematic if the files are moved to another volume.
Before importing files to FCP, one simple way to provide unique filenames is simply to use Finder's rename "format" function. It can take the existing filename and add an incrementing numeric suffix. Having unique filenames avoids ambiguity in post production, plus it enables FCP to relink those files even if they are moved to another drive. There are also some XML scenarios where unique filenames can help.
If all your disk volumes are not APFS or HFS+, your highest priority should be changing that. You will have to carefully back up all that material to another drive before reformatting the current drive. Using ExFAT drives is OK if used strictly as a "data shuttle", in fact many camera cards are ExFAT. However ExFAT should not be used for FCP data or libraries. It does have transactional protection for metadata, and it does not support inode address resolution.
Any system using a media database (Adobe Lightroom, Resolve, Premiere, formerly iTunes, etc) has problems if you rename or move a file. The goal with any such system is organize and query the material by metadata, not by filename. E.g, on FCP use keywords and ratings. If renaming files is necessary, do that BEFORE importing, not afterward.
FCP actually handles media better than most -- provided your volumes are APFS or HFS+. If your filenames are unique, FCP can relink those even if moved to another volume and put in different folders.
If your media filenames are unique and placed only on APFS or HFS+ volumes, you are unlikely to have a problem with missing media or relink. There are some exceptions to this such as externally-generated proxies or externally-transcoded media, but that's not what we're discussing here.
