If you use a Mac, I’ve really enjoyed using Divvy. You can define snap zones with keyboard shortcuts. It’s $20, but that’s worth it for me considering how much I use it.
https://apps.apple.com/us/app/divvy-window-manager/id4138575...
https://apps.apple.com/us/app/divvy-window-manager/id4138575...
You will need to do a little configuration, but it does the snap zones thing perfectly.
My memory is hazy but I feel this is close to some now-elided window management feature in MacOS...
Thanks for the tip!