How does it work on static, hard coded pages/ templates?

Hello,

I created a theme, where all the pages are static hard coded .php files, and they are “templates”.

They have a header image, normal tags.
They also have images in the background added as css background images.

Will this plugin optimize and render next-gen images for such pages?

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question 2:
does the “ONE-TIME 10K” package, work for sites with up to 10.000 images, or it is intended as 10.000 images downloads?

If I have a site with less than 100 images, would that package be good for me, or after some time, after some number of downloads or some other criteria will there be chances I go over 10k?

Thanks in advance