Cross-Domain Language Preference

I have a question about a cross-domain language preference requirement.
Now, I have a website "Domain1.com" and "Domain2.com" which are deployed and managed by Sitefinity.
Both of the websites have 3 languages for selection, English, French, German.

My requirement is that:
A user is viewing the Domain1.com in English.
When he is going to Domain2.com (either by typing an URL directly in browser or selecting an hyperlink from Domain1.com), he can be re-directed to the English site of Domain2.com automatically.

Can you please advise how to do this in Sitefinity?
Thanks.