Yes, step 3,4 can finish by ea,but hard backtest.
If let ea do it, below is my solution:
1) indication: atr, 2 MA
2) calc most trending pair with 2MA, such 5 , 10 ma,
Less crossing number and pips moved distance per unit time, such as 20 days move 1000 pips, MA no cross.
3) calc volatile with ATR
Backtest is hard as it use all the pair data.
If we judge by our eyes, it easy.
Such as most trending pair is usoil in the pass year