Is it legal to cheat a fraudster?

Can you defraud fraudsters?

I assume that this was a private sale & lpar; no return, etc. & rpar ;.
Then you'll be off the hook anyway if you can prove you sent the card.
At the moment you can obviously only prove that you sent "something", can you also prove the contents of the package?

If so, you don't really have to do anything else, because that's no longer your problem.
If PayPal causes trouble, I would let them know and send all the evidence.
If they still decide against you, THEN I would think twice about what you want to do.
At the same time, you can offer the buyer your first alternative. If he already pays in advance, then you initiate the transfer of the card, otherwise you simply do nothing.

Should PayPal decide against you, you can choose whether you want to bring your PayPal account to € 0 and reverse any direct debits that may have occurred, which causes a bit of trouble with PayPal, but this is mainly because you have the correct shipping and content ; & excl; & rpar; can prove & rpar; is not that bad, because they will not complain and if they do, then they will lose.

Or in this case you take your alternative 2, which nobody can blame you for, because strictly speaking it is still your number.
In this case, I would prioritize a little more in the direction of police investigations.

I would personally not do alternative 3 under any circumstances.

"My contributions only represent my point of view, no legal advice. All information without guarantee"