Most non KYC CEX have daily withdrawal limits. MEXC is definitely a good exchange but they have a withdrawal limit of 5BTC per day. Unfortunately, is not available for US citizens unless the OP can use VPN.
That's right and most of these non KYC cexes are also likely to change that rule of having a nonkyc account and limits. Soon, it's possible that they're going to remove those free(nonkyc) accounts.
In my opinion mexc is the best one out there but you can even use binance without full KYC, your limit will be low tough.
Maybe dex are the future, who knows, no KYC so far on metamask...
I don't use mexc but if that's the only option and it supports TRC20 USDT which is what OP needs, yes it does since 2 years ago and this is what I have seen:
MEXC now Supports USDC Deposit and Withdrawal on Tron Network(TRC-20)