Yep, you’re gonna find that most of the good stuff points back to scripting.
Is your goal just to select the items? Or are you planning to do something with the results afterward?
This script uses Everything to find duplicates (for example, based on the sizes of the selected files) and puts them into a collection.
With this other one, you can actually filter by size (even in expanded folders, etc.), but you have to type in the size or range you want to use.