The only translator who worked directly with Borges was Norman Thomas de Giovanni. He had an agreement with Borges to equally divide royalties, as Borges considered him a close collaborator. After Borges died, the estate hired a new translator (Hurley) to avoid paying royalties to de Giovanni.

It takes a bit of effort to find Borges-approved translations, as they are out of print, https://news.ycombinator.com/item?id=8310591