Too slow while simulating the contract deployed on mainnet

[UselessXiaoYao]

Recently, I have an idea to simulate some contracts that deployed on mainnet, in order to get tax, price and such things about them.
But when I test it, I found the efficiency is too low.
For example, I designed a progress to get the tax of sell/buy/transfer of the token MOROS(0xab85fc558d722a2b7c040ffb77db676bd9e7d322), but the transfer function call consume almost 6 seconds once.
And I watched my machine resource of CPU/MEM/Network, none of them ran out of.
Below is a piece of my code:

async function CheckTokeTax(targetTokenAddress, targetTokenABI) {
    ...
    const lpAddress = await uniswapV2Factory.getPair(WETH_ADDRESS, targetTokenAddress);
    // prepare simulate transactions
    const amountWei = 100000;
    const buySigner = await ethers.getImpersonatedSigner(lpAddress);
    const symbol = await tokenContract.connect(buySigner).symbol();
    const lpBalance = await tokenContract.balanceOf(lpAddress);
    console.log(`Pair Contract Address: ${lpAddress}, Balance Before Buy: ${ethers.formatEther(lpBalance)} ${symbol}`);
    const toBalanceBefore = await tokenContract.connect(buySigner).balanceOf(account_to);
    console.log(`Balance Before Buy: ${ethers.formatEther(toBalanceBefore)} ${symbol}`);

    // buy
    const balanceEthPair = await localProvider.getBalance(lpAddress);
    if(balanceEthPair < ethers.parseEther("1.0")) {
        helpers.setBalance(lpAddress, ethers.parseEther("10.0"));
    }
    // transfer spend more than 5 seconds
   console.time("transfer)
    const txBuy = await tokenContract.connect(buySigner).transfer(account_to, amountWei);
    console.timeEnd("transfer")
    const buyRes = await txBuy.wait();

    const lpBalanceAfter = await tokenContract.connect(buySigner).balanceOf(lpAddress);
    const toBalanceAfter = await tokenContract.connect(buySigner).balanceOf(account_to);
    console.log(`Balance after Buy: ${ethers.formatEther(toBalanceAfter)} ${symbol}`);
    const diffValueBuy = amountWei - Number(toBalanceAfter - toBalanceBefore);
    const taxRateBuy = diffValueBuy / amountWei;
    const taxInPercentBuy = taxRateBuy * 100;
    console.log(`Buy Tax: ${taxRateBuy}, ${taxInPercentBuy}%`);
}

So, whether it's a wrong way to do such simulations? Or is there a fast solutions?