I think the only way to tackle Apple's app redundancy policy (where just about every app that is older than a few months has to be made redundant with each update and the developer has to come out of retirement and run behind Apple to re-code it or spend $$$$ to code a 64bit version of it)
is use the free VirtualBox with Windows (you can get a Window 10 product key on eBay cheap for a new install only) and use the Windows version of the app, use VirtualBox with an older version of Mac maybe with Rosetta even for PPC apps.
If you don't mind paying for a virtual machine look at Run 32-bit apps on Catalina with Parallels Desktop®

Apple fined for slowing down old iPhones

See the link under this video to download VirtualBox High Sierra VMDK
https://www.youtube.com/watch?v=VhbMyn9iI98



https://www.youtube.com/watch?v=-b6yaKVOwzA