I have not had any difficulty with correlation, I do not keep track of that.
I have quite a few different kinds of Ea's that I work with and many of them are on EURUSD charts.
Theoretically I guess a person needs to avoid correlation, but I have not found that to be critical up until now.
I have no idea what others feel about this or how they manage their portfolio, and I am no expert in this
The more I think about this topic, the more questions arise...
I would have to ponder a long list of advantages and disadvantages of this approach.
I can see that it would be very time consuming but there may be some reward in satisfaction.
(I have one ea that trades multiple setups simultaneously, all on EURUSD, using only the price channel as the indicator, and that ea is what I count on every day to produce what i want for income. I think that may be why I am a bit skeptical about spending a lot of time on correlation. The money is made by keeping things optimized and observing performance closely.)
You only need a few strategies to make your money.
Again, these are only opinions and we all see the markets differently. That is what makes trading to be so much fun.