The QRC20 supports deployment and linking across multiple shards, so if you want to deploy a multi-chain token you'll need to use the QRC20 contract and link all of your deployments. However, developers can use ERC20 contracts to deploy on a single chain.
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To deploy smart contracts with cross chain functionality, you need to use the SolidityX compiler which is accessible in hardhat via the quai-hardhat-plugin npm package.
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For more developer resources, please visit our developer documention.