If you are willing to risk it:
"Retroactive is an app that lets you run Aperture, iPhoto, and iTunes on macOS Catalina."
https://github.com/cormiertyshawn895/RetroactiveBTW, for orphaned software like this, it would be nice of the source code were released; some enterprising folks might build an open source
64-bit Catalina compatible version.
If Apple coded according to its own highest standards (pure Cocoa not Carbon, etc.), that might require little more than recompiling.
