Photo syncing 29k photos from my Mac, only 13k appears in iCloud.com and other devices

Hello! I was used to managed my photos with Aperture. I imported the 29k photos of Aperture in Photo. Strangely, Photo shows up 29k photo in the device that managed the import, but less than 1/2 go them in the site iCloud.com and my other devices.

Maybe it comes from the fact I've "drag & dropped" some photos in Aperture (instead of importing them). If this is the problem, how could I load the full pictures into Photo/iCloud?

Thanks 4 your help, dear community ;=))

Serge