Language settings in the header

We have a multi domain website which uses header to set the language for different domains e.g. for MX the header has content-language=es-MX.

When we enable Wp Super cache (with Cache HTTP headers with page content option enabled), the page for https://hamiltonbeachcommercial.com seems to be working fine but if we try to load https://hamiltonbeachcommercial.mx it will load that page with Spanish text but it doesn’t load MX specific images but rather images from .com.

Is there a way to force caching of separate pages based on the content-language setting in the header?

Kind regards

Gabrijel

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