Transitioning from Standalone (Tweaker) install to Steam: Copying files to the Steam library directory?

My internet isn't the most stable or quick at the moment (Real world issues have nearly everyone in our area using Netflix or other video streaming services, etc.)

Is it probable that one could copy the files from the standalone install location over to the steam install location to prevent needing to download the lion's share of data once the 5th rolls around?

I still intend on using the Tweaker for options settings and such, but having the ability to use Steam for transactions and get bonuses to boot sounds super appealing.

I know the standard MS install will give a time-sensitive code you need to enter into the Steam version to link accounts, so I'm not uninstalling anything until I verify that my MS and Steam accounts are linked properly, at which point I presume I'll just be able to uninstall/delete the old data and point the Tweaker to the Steam install location.

Depends on how steam distributes its initial install. It might be the same 11gb that ms store starts with, just a matter of where it puts the files after, i imagine.