Okay, so to summarize — and I’m going to ignore most of the replies here — you need an older version of an app not previously acquired, and the current version of the app needs a newer macOS than your newest available Mac can run.
That’s means downloading older versions of the app is generally not feasible with the app store model.
So… what to do? Probably not buying a new Mac for this activity, so that means looking for Apple Configurator 2 app alternatives. (The number of apps that won’t work this far back or won’t work on Intel Macs is only going to be increasing, so you’re on this Mac upgrade path, regardless.)
You’ll probably want to try iMazing Configurator, which is part of the paid iMazing product. I think the profile editor is free. the iMazing app is cheaper.than a new Mac, too.
https://imazing.com/configurator
https://imazing.com/profile-editor
This open source app is roughly equivalent to Apple Configurator 2:
https://github.com/ProfileCreator/ProfileCreator
Above this range of apps, you’re headed for acquiring an MDM system, and there are some more expensive and more involved options there.
Oh, and a postscript: older versions of Apple Configurator 2 work just fine without T2. I am still using it on a iMac 2017 at ine site.