many services for selling ERC20 tokens in ancient times etheredelta was the main center but for now renamed to forkdelta other than that it can be sold on idex or large markets depending on the coin it can list Where, but if you have tried everything and the ERC20 coin you have no interest at all
means that the coin cannot be sold and is only a display in your wallet
Etheredelta has not been renamed. The owner of the exchange sold it to Chinese companies and, in parallel, it has launched a new exchange Forkdelta. They even had the same order books for a while. Now both of these exchanges are almost dead. At the moment the best solution for trade tokens is exchange Uniswap.