I have been using MEXC for a while now and when I log in it says that I should do a KYC before I do spot or future trading. There is no clear answer to questions in the chat.
But what also surprised me is that Kucoin is specified as the sender for transactions. Could it be that MEXC is a subsidiary of Kucoin and is now also subject to regulation?
Do you know anything else besides Poloniex? I will definitely test it but the no KYC exchanges are disappearing more and more.
I'm not aware of the relationship between KuCoin and MEXC, but don't expect too much from centralized exchanges offering non-KYC services. They're only non-KYC until they require you to go through it. You'd be disappointed because you already have funds in your account and they're held hostage, but it might actually happen anytime. You should know that right from the start. Whether MEXC is offering non-KYC services or not isn't the issue because KYC and AML have always been part of their ToS. The same with KuCoin. The same with Poloniex. The same with all centralized exchanges.
You can try the exchange at my signature. I have been using for a years and didn't encounter any issues. Use my link and you will get 2% rebate on every trade in exchange for it.

Are you promoting BingX? It doesn't have a good track record either. And don't be like them; don't mislead people in believing they can use such services without ever complying KYC.
"By creating an account on BingX, you agree to share personal information requested for the purposes of identity verification."
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https://bingx.com/en-us/support/articles/360033286474-CustomerAgreement/