You mean some service that works on the backend and allows you to send ERC-20 tokens without having ETH on the address right? Just deduct some of the tokens and send the necessary gas for the transaction from a smart contract that you can broadcast a message to. That would be amazing.
With the current source code that implemented on the Ethereum network, Triggering the smart contract was also need an Eth to pay the gas fee. Maybe in the future it was possible by only Signing the message? Or maybe implementing ERC865
https://github.com/ethereum/EIPs/issues/865 or EIP-1077
https://eips.ethereum.org/EIPS/eip-1077. I'm not an expert though but i suppose something like that right? Also for OP i will both of them for profit since it's have great potential.