Presales for exmage

Hello,

I have several domains with different extension that share the same images but with different alt tags.

approximately 60 Gb of product images but I need to have them on different domains + different alt tags.

So the question is:

If I have already downloaded the images to the main website XX.com how hard is to set up other sites to use the same images but to have different alt tags.

All sites are on one and the same VPS

best regards,
Itso