Where to Swap BTC for USDT

I bought some BTC back in 2015 and honestly forgot about it until recently. Now that I've got a kid on the way, I want to take a little profit nothing crazy, just enough to help give my child a good start.

The issue is my BTC came from mining and old wallets, so I'm not sure how to swap it without getting hit with verification requests or冻结 funds. I don't want to sell everything, just a portion to move into USDT for now.

Is there a clean way to do this without going through KYC? Not trying to hide anything, just want to avoid the headache of explaining old mining coins to exchanges. Any advice from people who've been through this?