We implemented the “pay with any asset with pool” feature in Taniko but seems like asset conversion is not working on Rococo or Westend Asset Hubs.
I tested with Polkadot and managed to put a remark onchain paying with DED (see extrinsic) but on the testnets the asset conversion runtime APIs return null and submitting an extrinsic gives an error 1010: Invalid Transaction: Inability to pay some fees , e.g. account balance too low.
Let me know if I should file an issue somewhere 