I’ve created a pretty straightforward Token system that would allow players who earned Challenge Mode sets in MoP to have them on other characters at the cost of temporarily revoking it from the character(s) who currently have it.
(Eg. If you currently had [Challenge Conqueror: Gold] on 3 characters, then those 3 will receive a Token each in their mail upon this change).
Since the [Challenge Conqueror: Gold] achievement is already “account-wide”, but with a vendor restriction per-character, bypassing that entirely by just adding all 11 Challenge Mode Class sets to your appearance/sets window (for each class appropriately). You still wouldn’t be able to actually use any of them though unless your character is in possession of the token (much like how you can have the appearance of Engineer Goggles, but if you don’t actually have the profession skill, you can’t mog into it).
Why this change?
It’s been a zugging decade since MoP Challenge modes, and there’s a pretty high chance that many players who got CM Gold back in MoP aren’t even playing those toons as their mains anymore. Anecdotally, my entire friend group that I did the challenge modes with, for example.
Be it, undesired class changes, boredom, or changing tastes/preferences etc, the reality is that this game is so account-wide in so many aspects, but strangely restrictive in others, and if I can ride the CM Silver Phoenix mounts on any character, why not let me at least switch privilege rights? I’ve only got 2 CM sets myself, but both my Monk and Shaman haven’t seen any active play since Legion. I’d happily revoke their access to the CM sets if it meant giving it to this Warrior, or my Paladin or Priest.
Players who got CM 11/11, or already have it on their preferred characters wouldn’t be affected by this at all- you would just get the Tokens upon login and simply need to drop it off in Void Storage. All this really does is let you use what you earned on what you’re playing pretty much. Mailing to alts is on a 120 day cooldown so that this isn’t something you just change on a whim every other day (kind of like how Item Restoration is on a 7-day lock also).
Blizzard are realizing that when we can access the stuff we worked for one the characters we currently play, everyone wins. I think this rationale was why achievements & mounts became account-bound in the first place, why the Balance of Power Artifact weapon appearances are now going to be account-wide so long as you did it once, and why they switched from class sets to weapons for WoD’s CM. At the end of the day, if you put in the time, you should be able to reap the rewards- and in a game like this where class changing is pretty common to do expansion-by-expansion, I think the original CM set limitations are a relic of a bygone era for WoW.