quick question: have you tested these sites? in case your answer is "yes" I would like to know:
1 - what was the capital you used?
2 - what is your daily return?
until recently i tried Arbitrage with an altcoin, but the withdrawn fee was high and days later the exchange deactivated the altcoin withdrawn. and from what i saw this problem of destabilizing the withdrawn of altcoins Is a big obstacle to do Arbitrage
Yes . cfolo.com is free and you just pop-in and search any pair you need
from my personal experience with them. i only choice trusted exchanges from their list

you can select exchanges and it will show up profit . or you can use "Revenue calculator" to find profit calculator
I also have to deducted withdraw fee from every time i do swap.
My advice : do not try with small amount because withdraw fee from exchanges could make no profit for swap.