I'd probably start by setting one array as the resulting intersection list, and comparing each array to that one.
my @arrays = ([...], [...], [...]);
my %tmp_int;
# assume intersection is entirety of first array
# and set each "frequency" to the number of arrays
@tmp_int{@{ $arrays[0] }) = (@arrays+0) x @{ $arrays[0] };
# then check the other arrays against it
for my $set (@arrays[1..$#arrays]) {
my %seen;
$tmp_int{$_}-- for grep { !$seen{$_} } @$set;
}
# the ACTUAL intersection is all the
# keys in the hash whose value is 1
my @intersection = grep { $tmp_int{$_} == 1 } keys %tmp_int;
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