Well, an automated process would be nice, but you can do that in just a few steps, if you are careful. Including the existing order in the new Playlist adds a level of challenge, but you can just include the steps from
your other thread. I think using the Episode field works best here.
This is one version of a procedure that works. Someone might be able to come up with an easier version, but this meets all your requirements.
1. Select the Playlist that you want to upgrade to the best versions of Tracks you own.
I tested with a Playlist of just one Album of 10
MP3 files, "Let Love In" by "Nick Cave & The Bad Seeds". I shuffled the Playlist so that it wasn't in Track number sequence to prove the test.
2. Copy your source Playlist to a new Playlist, as things can go wrong if you miss or mess up a step, and that can result in your source Playlist getting updates you don't want.
My new Playlist was named "Low Res version Playlist".
3. Show the [Episode] column in the Playlist. Select all tracks and then edit the [Episode] column, and enter "=Counter()". That will save the Track sequence for use in the following steps.
4. Create an empty Audio View and link it to the new Playlist above using the "Playlist ... is any ... {the Playlist you created in 2 above}" In my case, "Low Res version Playlist". Save that with an appropriate name and display the View.
I named my View "Up Res a Playlist". The View correctly showed 10 files.
5. Select all 10 files and press Ctrl+C to copy the tags from these files. We want the Episode tag for later.
Note: Do not resort the Playlist or View after this step, as the sequence is important later.
6. Enter the following search expression in the Search Bar, top right, for the View. "~expand=Name ~dup=[Artist],[Album],[Name]". No quotes.
As I have APE, MP3, FLAC, and M4A versions of these files, for just such testing, the View now displayed 40 files, 10 of each type.
The
~expand=Name function can result in unwanted files being added to the View. For example, the Album I chose has a Track named "Do You Love Me". Not an uncommon name, so as we are expanding the files to include based only on the name, any other Tracks with that name will be included.
The
~dup=[Artist],[Album],[Name] function limits the tracks in the View to just duplicates, matching on Artist, Album, and Track names. Any unwanted Tracks included by the ~expand function should now have been removed.
7. Select all 40 Tracks in the View, right-click on one and select "Send To > Playlist > {the Playlist you created in 2 above}". Note that the Playlist you are working with will probably be at the top of the "Send To" menu, so you can just select it there.
8. Select all 40 Tracks in the View, right-click on one and select "Stacks > Advanced > Autostack Files by Artist, Album, Name". In popup "Stack Top" dialogue, select "No" so that MC will pick the largest, and hence the highest resolution, file automatically.
The View will be empty after this step. That's expected and correct.
9. Clear the Search Bar expression, easiest by clicking on the X on the right end of the Search Bar.
The highest resolution files for the original Tracks will now be displayed in the View. The quantity should match the number in the original Playlist. The sequence of Tracks should also match the original Playlist. Check if you like.
9. Select all Tracks in the View. Press Ctrl+Shift+V to paste the Episode values. Click the "Check None" button, and then select just the [Episode] field. You could choose to paste additional fields here, if desired. For example, you may want to paste [Last Played], [Last Skipped], [Number Plays], and [Skip Count] so that the playing history from the low resolution files is retained for the high resolution files. You may also want to paste [Lyrics] to save looking them up again.
10. With the files still selected, right-click on one and select "Send To > Playlist > Create Playlist < {enter a name for you new Playlist that includes Hi Res versions of the original Tracks} > enter".
I called mine "Fixed Playlist of Hi Res".
11. Open the new Playlist, add in the [Episode] column to see the values posted above. Sort by the [Episode] column. Click the "Update Order" button to save the new sequence to this Playlist, which will now match the original Playlist sequence.
Done. Easy really, huh?
Test this carefully before applying it to your large Playlist. Make sure to test it with a good mix of files. Every step is required, exactly as documented. I ran through the process quite a few times, so I'm not testing it any more!
By the way, I'm not sure if the "Swag of Tools" or "MCUtils" toolsets would make this easier. I wanted to see if it could be done in standard MC.