Fix all the image uploaded in a single folder

Hello to everyone,

i’m facing a problem, a site that i recently started to manage was used so that all the images (over 10.000 images) are upload in the upload folder, without subfolder like month, day and so on.

While i immediatly fixed it in the setting all the previusly upload images remain in the same folder, this is troublesome and i suspect is contributing to the incredibile slow loading time of the site.

Is there a way to move all the images in the standard (or custom created) folder without breaking every image link?

Thanks in advance for any help