Are you looking for something like:

use strict;
use warnings;

my $line = 'one="1" two="2" three="3" x="y"';
my @parts = $line =~ /([^=]* = \s* "[^"]*" )\s*/gx;

print "$_\n" for @parts;
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Prints:

one="1"
two="2"
three="3"
x="y"
[download]