Man pages matching name systemd-sysusers in section 8:

systemd-sysusers.8.de	debian 10 / manpages-de
systemd-sysusers.8.en	debian 10 / systemd
systemd-sysusers.8.de	debian 11 / manpages-de
systemd-sysusers.8.en	debian 11 / systemd
systemd-sysusers.8.de	debian 12 / manpages-de
systemd-sysusers.8.en	debian 12 / systemd
systemd-sysusers.8.en	debian 12 / systemd-standalone-sysusers