How to download PERMANENTLY some files from iCloud.

I have correctly setup my iCloud account on my MacBook Pro Retina running MacOs 10.14.3.

I have many files saved in iCloud Drive (2Tb subscription). There's a specific folder, that I don't use so often, but I MUST have those files when I need them. (With or with out internet).

As I don't use them too often, iCloud "upload" them and I need to click on the cloud icon and download them again. That happens, because I have "Optimize storage" turned on. I need that option because its a 128Gb Mac. There's no problem if iCloud "upload" other files to the cloud to optimize storage, but not this.

How can I keep "Optimize Storage" and also keep this files always on my computer. Is there any way to mark as, I don't know, "Important Files" or "Keep it Files"?