Correlation between 2 pairs ea for rebate

I need an ea that work in 2  pairs (for example EURUSD USDCHF) After opening 2 trade in opposite direction, the ea have to open other positions to recover the drawdown. Example 1 lot buy in eur usd and 1 lot sell in usdchf Calculating the spread and swap there will be a drawdown , at that point the ea open other positions for 1, 20 eur usd and 0.80 lot un usdchf.The goal of the ea is to open  as much lot as possible , always monitoring drawdown between this 2 pairs. These pairs are just an example, i need 2 pairs strongly correlated.The drawdown have to be always under control , opening position to cover the eventualy drawdown. If there is some profit we can proceed with a trailing stop. Remember the goal is rebate and lot , we can accept no profit and no loss