In this case you can do P2P transactions. Binance or kucoin exchange will give you such facility. P2P transaction system is much safer than third party transactions. After making an account in the two exchanges that I have mentioned, verify the exchange. After verifying the account, you will convert the BTC or other currencies that you have, that is, the ones you want to sell to USDT or BTC. After transferring your funds in the P2P section, you can easily sell your BTC or USDT by placing an order of your choice.
I still don't know why op is not interested in using an exchange and moreover if he is not ready to do KYC, he should have stated it clear because many persons does not like dropping there information on an exchange to avoid it being compromised. If he want to do escrow service, that's fine but he will have to drop his bank information to the persons he would be exchanging Bitcoin with, whether to covert it to dollar or other currency depending on his region. There are also people here that can swap his Bitcoin to fiat if that's what he is looking for which could be very easy for him.