How to sort the latest data files from two to one computers?

Ver 21H2
Build 22000.1098

Problem: How to Select the latest file when copying two identical dir/subdir sets from a Win7 machine and a Win10 machine to a new Win11 machine?

A long unnecessary backstory has resulted in some Excel/Word work (~8 GB is the entire set size) being done using both the Win7 and Win10 machines over several months. Going forward, once a copy/paste of the teased out C:\Documents\... is finished to the new Win11 desktop and laptop the older machines will be retired.

I can picture on one of the new Win11 machines having two instances of explorer open representing the two older document sets machines and each explorer open to C:\documents and "something" then able to automatically run both explorers teasing out whichever has the newest file date and then including that file amongst those allowed to migrate.

There are some files that may exist on the Win7 but not the Win10 (and vise versa) and those orphan files would be included in the above process.
Is there a util that would solve the problem?

Mark

I've done similar by plugging in a suitable-sized USB Thumb drive or even a USB External HDD, creating a folder named for one computer, doing the same for the second computer then copy the files as appropriate. I also create or copy the same folder on the new computer. By having the folders on the Thumb drive it also serves as a backup.

One could simply copy all the folders in C:\Users\USERNAMEHERE as needed to work with later but there may be a few files that won't copy such as ntuser.dat.

I'm able to do it by copying all desired to a NAS drive which can be accessed from any computer I wish.