How do I import old photos without them all showing up in Recent folder

I have 5000 photos from 2012-2014 that I would like to import to my icloud library just to have memories of those years accessible on the cloud. I like that you can go back in the years and see photos in chronological order.

Currently these pictures are in a finder folder on an external hard drive.

What I'd like to do is import all 5000 photos into my library. BUT. I don't want all 5000 photos show up in my Recent folder. I tested it out by dropping one photo from finder into the Photos app. It syncs up perfectly on my phone but it comes up as the most recent picture in my recent folder in my phone. I don't want that to happen to all 5000.

Can anyone help?

Thanks!