Somewhat crude, but passes your test cases without false positives: 
use strict;
use warnings;
use feature "say";


while (<DATA>){
    my @ips = m/\(([\d\.:]+)[\s<>]*([\d\.:]+)?[\s<>]*([\d\.:]+)?\)/;
    $_ and say "$.  >$_<" for @ips;
}

__DATA__
email
(209.85.208.68)
(172.217.194.27 < 209.85.208.68)
(172.217.194.27 < 2001:4860:4860:0:0:0:0:8888)
(2001:4860:4860:0:0:0:0:8888)
(2001:4860:4860:0:0:0:0:8888 < 2001:4860:4860::8844)
(2001:4860:4860:0:0:0:0:8888 < 172.217.194.27)
(2001:4860:4860:0:0:0:0:9999 < 172.217.194.29 Not terminated by close 
+paren
Sometimes, it appears in this way too. It may have IPV6 as well.
(172.217.194.27 < 172.217.194.27 < 209.85.208.68)
Anyway, I stared with below. It won't fulfill. It can catch ipv

[download]
Output: 
2  >209.85.208.68<
3  >172.217.194.27<
3  >209.85.208.68<
4  >172.217.194.27<
4  >2001:4860:4860:0:0:0:0:8888<
5  >2001:4860:4860:0:0:0:0:8888<
6  >2001:4860:4860:0:0:0:0:8888<
6  >2001:4860:4860::8844<
7  >2001:4860:4860:0:0:0:0:8888<
7  >172.217.194.27<
10  >172.217.194.27<
10  >172.217.194.27<
10  >209.85.208.68<

[download]

                Memory fault   --   brain fried

In reply to Re: Regex to catch IPV4 and IPV6 whenever ip appears withing brackets by NetWallah
in thread Regex to catch IPV4 and IPV6 whenever ip appears withing brackets by theravadamonk

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