No face-recognition within icloud - photos?

Hi, I'm using a macOS 15.2 and store all my photos within photos app. As i only have a M2-MacBook with 500 Gb so I activated "icloud-photos" any also the option "optimize mac storage". But now i realized, if a photo isn't locally stored with full resolution the face recognition process isn't executed. Neither on my Mac and also not within icloud. I got 2 TB of icloud space and I still have to buy another Harddrive to get access to basic functionality, this can't be real.

Any chance to solve this, to get the face recognition done, without buying another harddrive?