Correct. The current plan is that if you purchase a Relinquished token for, say, shoulders, and it gives you a legendary, it gives you legendary shoulders.
Massive wall of caveats here just because I don't want to over-promise:
This is PTR. Anything can change at any moment. Many things already have.
We don't have a solid handle yet on how long it will take to earn these things, or what the chance of them becoming a legendary will be. We need to be confident that the Broken Shore content itself is stabilized before we can start figuring out things like how quickly you earn Nethershards or how much these tokens cost.
Their primary purpose is still as catch-up gear, similar to what was available on the Timeless Isle or Hellfire Peninsula. We don't consider this a "silver bullet" solve to all legendary-related issues, and aren't trying to make it be one. Still, if you just desperately want that one specific legendary, this might be an option worth considering.
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