You can only do that with 'phones that are relatively well extended in FR already and are clean everywhere else but FR. EQ can rarely fix large frequency response errors at either end of the spectrum because the driver can rarely take such abuse. EQ won't make it decay any faster or cleaner either. Many IEMs actually meet those requirements fairly well so EQing them can usually be very effective but most full size 'phones don't.
kiteki has mastered skill: Cherrypicking
Look! I can use multicolored text too! Seriously kiteki...
You need to stop just looking at the graphs which have similar shapes. Why don't you look at the graphs which are different between them?
You need to understand what those graphs mean instead of just matching up shapes that look vaguely similar. Do you see how those square waves settle differently? That's pretty important.
Why are you ignoring the massive difference in FR above 10khz? While there's not a ton of information above 10khz nearly 30dB is a ton of extra SPL.
Why do you ignore me when I tell you that an individual graph or plot doesn't tell you everything about how they sound? You need to look at all the available data before making a conclusion and if there's not enough data available you might not be able to make one.
Why do you assume the IF and Headroom are the end all and be all of useful headroom measurements? Didn't I tell you about CSDs before? Have a look at how they're useful.