If it’s exploiting an unintended interaction or method for doing something that otherwise is time gated in some way it’s risky for sure. Idk how much they monitor legacy stuff, so it might be not really bad, but you need to weigh the risk vs reward. Iirc at least one person has gotten a ban of some sort for abusing legacy items and repeatable quests to hit a new level cap hours after expansion launch, so there’s an argument to be made it could be called an exploit. The delete and repeat part is where the problem may lie, rather than just doing it on legitimate alts them transferring and using them later.