It’s not just a translated website. It’s a completely separate deployment AFAICT.
The DiamondHands guys are in partnership with Boltz. They are using the Boltz codebase, but it's a completely distinct deployment AFAIK. Also, Boltz isn't completely open source, but uses a Business Source License that will completely free the software in 2027. In the meantime, the software can't be used in production, unless with Boltz' agreement. Hence the partnership with DH.