Man pages matching name mailq in section 1:

mailq.1.en	debian 10 / courier-mta
mailq.1.en	debian 10 / esmtp-run
mailq.1.ja	debian 10 / manpages-ja
mailq.1.en	debian 10 / nullmailer
mailq.1.en	debian 10 / postfix
mailq.1.en	debian 11 / courier-mta
mailq.1.en	debian 11 / esmtp-run
mailq.1.ja	debian 11 / manpages-ja
mailq.1.en	debian 11 / nullmailer
mailq.1.en	debian 11 / postfix
mailq.1.en	debian 12 / courier-mta
mailq.1.en	debian 12 / esmtp-run
mailq.1.ja	debian 12 / manpages-ja
mailq.1.en	debian 12 / nullmailer
mailq.1.en	debian 12 / postfix