how to change multiple song names AT THE SAME TIME in itunes v 12.9.5.5

I know how to change them one by one, but that is very time consuming. I have tried changing file name in finder, and even copying entire album folder from music folder to another location, deleting album from iTunes. Changing the names of files in copied folder in the other location and adding it again to iTunes, but it reverts to old names. For example I want to remove the album name from the beginning of every song name, so I can see song name on intone or music apps on my laptop AND iPad and iPhone where names are truncated. So change:

"Mozart: Così Fan Tutte, K 588 - Act 1: Smanie Implacabili"

To either:

"Act 1: Smanie Implacabili, Mozart: Così Fan Tutte, K 588"

Or

"Act 1: Smanie Implacabili"

Thank you, George