BSC, Polygon are cheapest, I'd also add Optimism to the list. Honestly, no need to use any site for this, just choose these networks and make your transaction.
I have stopped using Ethereum for making transactions long ago, even when it's gas fees are low, you still pay around 1 USD, which is still expensive compared to aforementioned networks.
3 days ago, I wanted making USDT transaction on my Tron wallet and I had $2 worth of TRX on my wallet to be used as fees, if it was some months back, I can make more than 3 transaction and have some TRX remaining but it seems that the crazy fees is now accross all the chain but they are preferable to some than will asked for more than half of your funds, I think I will go with matic as an option than the BSC you mention because matic is even more cheaper tha Binance smart chain right now.
I stopped using Ethereum long time ago since Abitrum literally do anything you want in Ethereum chain, just bridge your funds to Abitrum and make sure you finish all your transactions before bridging back to Ethereum, it safe fees and also safe you from transaction failure which will cost you extra. One of my biggest fear of using Ethereum chain is when you make a transaction on Ethereum and it failed, it will be dropped but the fees will be taken which is like stealing, no work was done but they took the fees, for what exactly. It's better to avoid any chain that asked for large fees.