When comparing local filenames to a tag source, there's one app (I can't remember which one!) that has a very useful feature. It will color the track names in color based on their similarity. For example if it looks like the track title is an exact match to the local filename, it will be colored in Green, or if they are similar (different spacing/punctuation/etc) it might be Yellow. The same could be done for track durations. If I can remember which app did/does that, I'll post an example screenshot.
I'm pretty sure the program I'm thinking of is MusicBrainz Picard. Screenshots don't show the feature very well. It has icons ranging from red to green based on exactness of match, but doesn't show on the same screenshot what it's matching against. It looks like a bad implementation of a potentially very helpful feature.
Do you speak about these MB Picard track status icons?
Mp3tag does not currently perform any matching between the local tracks and the metadata provided by sources such as MusicBrainz or Discogs.
You will need to manually adjust the order of your tracks to match the metadata.
From the documentation:
If you want to change the order of the track ↔ file mapping, use drag and drop in the file list of the results window or the Move up and Move down buttons to change the mapping.
This is not how it works in MB Picard.
You can see your local data embedded in your local files on the bottom left side of MB Picard as "Original Value".
On the bottom right side you can see the new metadata downloaded as "New Value" and how it will be applied to your local track when you save it.
The colour-coded track status icons show how "similar" your existing data is (all of them, not only the TITLE content!) to the metadata from the MB source.
Like I said, Picard's implementation isn't all that great.
I know the tracks can be manually moved up and down, that's unrelated. I'm not interested in having it try to match tracks to tags automatically. What I propose for MP3tag is to match like rows, in their current order. For example, if a tag source says track 1 title is "A Song Name", and the matching filename contains "A Song Name", color the title in green (or add an icon of some sort). It doesn't need to be an exact match, in fact it shouldn't look for exact matches. The filename might be "01 a song name" and it would still be a close enough match to mark it green. And the tag source says its length is 4:35, that too can be compared to the local file duration and if it's within an acceptable margin, color it green.
In one of my own programs I did a very basic "fuzzy" match implementation by removing all special characters, punctuation, spaces, etc from both strings, and then checking if the filename string contained the other string (because the filename includes much more than just that string I was looking for). That's good enough to work in 95% of cases, the other 5% can still be checked manually like you do currently.