Any help on the ethical implications of selling an ended coin?
This was a long time ago and honestly I do not remember what I did. But I remember it was on a decentralized exchange and you would just put the coins to be sold, no talking.
if it's on DEX, ethical or not isn't the issue here. It's the buyer's due diligence before buying the coin
by looking at the volume trades and simple google search on the coin's name,
he can find out the necessary information about the coin and make his own investment decision (buying the coin or not)