Bisq does not do USDT trades, only BTC and XMR
There is usdt trading and but is basically buying and selling. Bisq wouldn’t work perfectly for this. What I think OP needs is not even swapping but more of bridging because there is no usdt on bitcoin blockchain. Only centralized exchanges can actually do this effectively, decentralized platforms charges alot, so OP should simply use the centralized ones that do not require KYC, like the exch.cx or use one platform called the ChangeNOW which I have used before but wasn’t satisfying because it took a ample of time before the transaction dropped.