There are various p2p platforms for meeting people with whom you can exchange fiat for crypto (and vice-versa) directly. Some of these platforms include an escr

There are various p2p platforms for meeting people with whom you can exchange fiat for crypto (and vice-versa) directly. Some of these platforms include an escrow system (LocalBitcoins is the most well-known of that type, but I think it has KYC requirements), others rely on a 'web of trust' style system, etc.