By design, rules are only applied on first import.
And it's unclear how it being otherwise could be construed as a feature...
Quick tests confirm No auto-tags applied in the following cases:
- An internal rename or move
There might be an argument for a use-case where files are imported from one source, then moved internally to where they "belong"—but that seems a rather backward workflow. (How do you know where they belong if they haven't been tagged?) Nevertheless, in that case, having rules applied would be convenient. In general, however, tags changing just because a file is moved or renamed would be unexpected and therefore problematic.
- An external rename or move
I'm not sure I understand exactly how it works, but MC is designed to recover from files being renamed
or moved externally. That is, the original records are maintained and the filename references are updated. In this case, just like the internal rename or move, it doesn't make sense to be applying import rules. On the other hand, if a file is renamed
and moved, MC cannot associate it with the original library record, so it will be removed and the "new" file imported. This means, for example, an episode could be renamed as a movie and moved from a series folder to a movie folder. As a result, the episode record would be removed and the file would be imported and tagged (according to the rules) as a movie. In other words, how the program currently responds to external changes is probably what most would expect and want.
Also, having these rules applied after import would preclude their use for setting "default" values for tags. For example, one might prefer not to distinguish adult movies in the file system, but manually set [Media Sub Type]=[Adult] after import. That would not be possible if the import rules were applied after import.
So, if there is a missing feature, I think it's a strictly manual command to
Update Tags (using import rules). This would update tags according to whatever rules apply to the file's current media type and file path.