I helped a friend to swap ETH to BTC on Trezor yesterday. It was about 520usd in ETH and received 486usd in BTC (fixed rate, not custom). From the suppliers there were 3 kyc and 2 non kyc. This was done through Letsexchange service non kyc. I don't know if the fee would be less on higher amounts, or through kyc services, but for this amounts seems quite expensive. Is it because of the gas fee of ETH or the tx fee of the service?

Anyway, at least it is an easy tool to do inside the trezor Suite on a more secure way between crosschains. The final confirmation was done 8-10hs later.