I believe, if user is setting asset as fee payment, this transaction should be already paid in new currency. This is not the case for erc20 Comparing this two operations its clear that changing to DOT, i paid already fee in DOT When i was switching to Hollar, i was still charged in HUSDx https://polkadot.js.org/apps/?rpc=wss%3A%2F%2F2.lark.hydration.cloud#/explorer/query/0xb1584591b7c7fa426383fd6618c45abeadaa8b785edf4b4311be62660295552b https://polkadot.js.org/apps/?rpc=wss%3A%2F%2F2.lark.hydration.cloud#/explorer/query/0x637acd2dc1b7c7cf124e14407ccb7fb372101c1b00d67ba385794ca13eae1096