I have a simple suggestion to resolve some part of this issue:
Pick every outfit and accessoires from the exploided outfit-chests and send it to every character, yes not every account, every character.
That would calm down the players that spend real money to get those.
To sort out which player got what and when would be imo way too much work on your side und nobody could seriously demand that.
But those people, that spend real money to get those outfits need to get those back, there is no room for debate! That is, of course, that some
overcompensation and the outfits must be unable to salvage into threats, but would be ino a step in the right direction.
The other issue is the removal of every other items.
I think it would be too much work to sort everything out 100%, so a simplier solution would be necessary.
Maybe a Package with 25-50 accountbound pet packs per account, or something like that, might be worth considering.