Photos importing to both 'Imports' and a specific album

You can drag pictures into Photos for import. If you drag them to the Photos icon, then the pictures will go into the general Library but not into any specific album. Just like with the File>Import routine, Photos will check for duplicates, and you will get a chance to OK the pictures or cancel.

But if you drag pictures into an open album, they will go there directly after checking for duplicates.

Are you maybe dragging the pictures to the Photos Window of an Album? What happens if you drag them to the Photos icon?

Since I'm still in Sequoia, I may be missing new tricks, of course…

Are you importing selected, single images?

It is easier to import photos from a folder by selecting a folder in the Finder in the Import dialog. like this:

• Click File > Import
• Then select a folder in the Finder in the File chooser dialog and click "check for import"
• You will now see a panel, where you can select the album, where the items from the selected folder will be added to. You can select or create an album or check "Keep folder organization".

If you want to select single files without adding them to an album, drag them from the Finder onto the word "Library" in the sidebar of Photos.

Do you have that album open at the time you do the import? That would explain it.

Maybe instead of telling us one important thing per post, you could let us in on it all at once? Here's a start:

• Does your SD port on the MacBook not work?
• Are you using iCloud Photos to synchronize your devices? If so
• …Do you have “Optimize Storage” checked in Photos’ Settings
• …Do you have more than 10% free storage on your iCloud account?
• Where does your Mac's Photos Library reside-- in the Pictures folder of your internal drive, or on an external drive? or on a network? on iCloud drive?
• Do you have more than 10% free storage on your Mac?
• Do you have that album open at the time you do the import?
• Has this problem always existed, or did it just start? Can you think of anything that changed that might affect your device?
• Does re-starting the Mac help?
• Does restarting the Mac in Safe Mode help?

           Start up your Mac in safe mode - Apple Support 

• Does Photos do what you expect if you use a different Library?
• Does Photos do what you expect if you work from a different User account?