不使用 ETH 转移 ERC20 代币

Question

I would like to transfer ERC20 tokens from a wallet who don't own ETH to another wallet who own ETH and who can pay gas fee. Do you know if it is possible to made a transfer of ERC20 tokens and to let the receiver wallet pay fees?

Answer 1

TLDR: Not possible, unless the token contract explicitly allows it. Or unless the token holder is also the block producer.

Transaction fees are paid in ETH (or generally, native currency of the network - for example BNB on Binance Smart Chain, MATIC on Polygon, ...). So in most cases, you need to pay ETH to execute either the transfer() function if you want to send the tokens from your address, or the approve() function if you want someone else to transfer tokens from your address.

Very few token contracts implement delegated transfer mechanism on top of the ERC20 standard. There's currently no standardized way to perform a delegated transfer, so each contract might have a different implementation. The token holder uses their private key to sign a predetermined message saying how many tokens they want to transfer to which address. The message also usually contains a nonce or a timestamp to prevent signature replay attack. Token holder passes the message offchain to the transaction sender, and then the transaction sender executes a function of the token contract built specifically for delegated transfers (note that the transaction sender pays the fee to execute this function). The contract validates the signature, and performs the transfer. Again, most token contracts do not implement this mechanism.

One more exception from the rule is a block producer. When you create a new block, you can fill it with transactions not only from the mempool but also with your own transactions. You can build a transaction with 0 gas price, and then include it in the block that you're producing. This way you're also able to send tokens for free.