Have you seen stable coin that lowset transaction Fee?
for transfer money between two wallet, which one altcoin or stable coin your choois? (lowset transaction Fee)
You accept stable coins and other altcoins so please look at two websites.
The first one give you list of withdrawal fees not transaction fees. However if withdrawal fee is cheap or free, it is consequence of cheap transaction fee.
The second website is esitmated cost for 51% attack on network of cryptocurrency. If a network has too low hashrate, it is note safe to move your fund. It is important if you move big fund.
1.
https://withdrawalfees.com/.
2.
https://www.crypto51.app/Stablecoin. I think Tether USD (USDT) on TRC20 chain is good (not 100% free but cheap and fast). BUSD is good too and with Binance Smart Chain, you will have cheap transaction fee
https://bscscan.com/token/0xe9e7cea3dedca5984780bafc599bd69add087d56