[BetterRed]

@rolk - IMO you're expecting the title_sort column to behave in a manner that's contrary to its design purpose.

I would advise separating the "[SomeCategoryName - Number]" part of your titles into a discrete custom column - eg mycategory. Maybe based on calibres Series type column. You should then be able to use a regular expression in Bulk Metadata Edit Search and Replace to remove it from the Title column, and put it in the mycategory column .

Then you could create another custom column (column built from other columns) - egg mytitlesort. It would built via a template that wrapped the mycategory in brackets and appending title_sort. But that said, I would question why you'd want do that. If its for sorting, then maybe the View Manager would be a better solution for you. If its for Send to Device and/or Save to Disk then Send To and/or Save As templates/plugboards would be a better solution - its what they're designed to do.

BR