Would it be possible at some point for ETH transactions on DEFI (swapping to ETH only) to require no ETH/Gas up front, but instead simply front it via a smart contract and take a fee out of the transaction?

If you have wallets with multiple coins and want to swap everything in to ETH, it’s obviously not possible unless you have ETH to begin with. How about a smart contract that can verify you have valid coins committed to swap and it fronts the ETH designated for the tx for a nominal fee?

Maybe this exists already. I haven’t found it yet.