Use !whois-ip6 to lookup Whois Registration Data for IPv6 Addresses.

Whois registration data for Internet Protocol (IP) numbers are maintained by the Regional Internet Registries and contain registrant contact points along with technical details for each IP number registration.

Usually, you do not prefix your query with !whois-ip6 or !whois-ip and !whois should work just fine.

Usage Examples:
!whois 2A00:1450:4001:C15::66
!whois 2001:420:1101:1::185
!whois 2606:4700::6810:85E5
!whois 2620:1EC:33::10
!whois 2600:1480:4800::41
!whois 2A00:0000:daf0:e:de::
!whois 2001:A000:Ba11::
!whois-ip6 FFFF::2dae:feed:dead:beef
!whois-ip6 2001:2345:6789:abcd:ef::
!whois-ip6 2001:4200:AFaf:AfaF:afAF:ed::
!whois-ip6 2001:1200::0012:1002
!whois-ip6 ::FFFF:8190:3426
!whois-ip 2a03:2880:f37c:1:face:b00c:0:25de
!whois-ip 2A02:6B8:A::A

Also see:
!help !whois
!help !rdap

  
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