I'm planning on exchanging some btc for monero and/or litecoin so I can make online purchases with crypto for low network fee. I'm just looking for an exchange that doesn't require KYC where I can exchange btc for one of these altcoins, and get the best exchange rate. What are the best options? I'll consider DEX or CEX, whichever gives the best deal.
From the DEX options, I think Bisq is one of the popular ones.
From the CEX options I have used Poloniex (poloniex.com) in the past to buy XMR. They do not have mandatory KYC (but have optional KYC for higher withdrawal limits) and supports Monero. They have spot pairs for XMR/BTC, XMR/USDT and XMR/USDC which you can trade without KYC. I think that their limit for No-KYC withdrawals is $10,000/day.
On the negative side, Poloniex has been hacked twice, so you shouldn't keep large amounts of crypto in your wallet there unless you plan to trade actively there (but then again that is true of any CEX). And there is always the risk that they may suddenly block your account and request KYC if they decide that your activity is suspicious, although this hasn't happened to me.