There are a lot of possible solutions.
You could just hire someone to help you translate the site and pay him xy/hour and keep all the revenues for yourself.
Or, as you suggested, you could setup some kind of JV. Just make sure it's a simple solution where accounting is clear and where both parties have some kind of "security" for their work. For example, if you own the domain and someone spends xy hours developing a subdomain in another language, how can he be sure he'll still earn money from is work in the future?
One JV I did, which is similar to yours, was this:
Someone had a great looking website with great content in English. He gave me the rights to use the design + the content and to translate it to another language. He setup the site with his design and the hosting.
I registered the domain and did all the work on translation + maintaining the site (changing aff programs etc).
So his cost are basically 0, and his work after initial setup was also close to 0, but I was able to use his design+content.
So what solution did we chose to distribute the revenues? Our simple solution: we just split the revenues 50-50. And instead of creating new JV aff-accounts, or giving eachother access to the other accounts to check everything is fine, we just setup a solution where clicks of users get sent 50% of the time to his aff-links and 50% of the time to my aff-links.
A simple solution, and it's still working after 6+ years...
"Semper paratus!"
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