Transferring Lightroom photo folders to new external hard drives

[bob_estremera]

Running out of space on my 3TB WD hard drives and need to purchase 2, 6TB units, one to work from and one for a backup.
Most all of the images I work with are on a folder named 'Categories' that only takes up 1TB. The rest are photos I almost never use.
I was wondering if I could just copy and paste or do a backup from the old external to the new ones with only the Categories folder.  That way the unused photos will still reside on the older, 3TB externals and the new drives will be more streamlined with only the active, Categories folder. My worry is that Lightroom might need the established folder hierarchy to 'find' all the images and that are in the LR directories now.
Am I making it more complicated? Should I just leave everything as is and move the entire 3TB contents to the new 6TB drives. Will LR find and open the images on the new drive or will I need to import all photos for each folder I work from?

Thanks,

[digitaldog]

https://www.lightroomqueen.com/how-move-lightroom-to-new-computer/

[JDMvW]

While you're buying new storage, why limit it to 2,6 TB? Storage is remarkably cheap these days; and what you have will invariably, sooner than you think, fill what you've got.