In a healthy company, I don't think you can outsource any work on the core product without making the end result worse. Even things like translations need lots of back and forth and the feedback loop needs to be really tight. It has to be clear to the user in the culture what you want to say and the things are very subtle at times, like the eye icon in the password field to show the password. In some cultures, that might be associated with something creepy or negative maybe, but you just don't know. Show or hide may be twice as long as in the languages you know which breaks your assumptions and makes the slick UI less slick or the error messages less clear in that particular setting.