I'm fine with a near-identical replica that any 2h sword capable toon can use, because replica, because it's obtainable. Time-travel is BS and can mcguffin anything in existance, and it's BS.
Even the DH warglaives are pretty BS, HOWEVER, the original pair was required to obtain the achievement for the mog skin. Compounding that problem won't help. Class locking legendaries is BS, when they largely aren't. Atiesh is an exception, but has also been unobtainable forever by now.
By all means, advocate for a replica, and let it be crystal clear that it is a replica (in my mind, ideally not the exact same as the original), that is a-ok in my book, as long as class-locking it is off the table.
In the same turn, warglaives should also be unlockable for mogging by any class that can use 1h swords, as that is what they were originally.