And I have a more specific question: is there some real atomic swap software that can do atomic swap beetween BTC and USDT (and vice-versa)? Or is it technically infeasible because the two coins use differente algorithms? If if's not possible, is there some stablecoin that can be swapped with BTC ?
I don't like Tether and I wouldn't use it for holding any funds because it can be frozen by central authority, and regulators are probably going to ban it sooner or later.
Liquality extension supports this atomic swap, but volume is low and you would probably pay extremly high fees for ethereum network transaction.
AtomicDex is offering atomic swaps but currently there is volume only for USDT on binance chain if you want to swap with BTC, but you need to have some BNB coin for this transaction.