Hmm, if I do this:

$str = '
According  to a researcher at an English university, it doesn\'t 
matter in what order the letters in a word are.';
$str =~ s/(\w)(\w+)/split"",$2;$,="";$,.=splice@_,rand@_,1while@_;$1.$
+,/eg;
print $str;
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I get "Anogdcric to a reecasrreh at an Enghsli uyirenvist, it dnseo't matter in wtha oderr teh leettrs in a wdor are."

Which doesn't fit the brief.

Some words are not mangled, and nearly all of them have the wrong last letter.

---

($_='kkvvttuubbooppuuiiffssqqffssmmiibbddllffss')
 =~y~b-v~a-z~s;                             print
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