I know that many countries make you pay taxes for the profit on crypto. That's when you convert into fiat. But taxes at conversion crypto to crypto? That's insanely stupid.
But for crypto-to-crypto there are still exchanges where you don't need KYC  under certain daily amounts, find some reputable ones for that (Binance can be an option).
And of course, there are the decentralized exchanges, DEXes, which are P2P, but I don't have enough experience on those to tell more.