These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.55 s (backtrack: 0/20).

[ebuild     U  ] sys-apps/shadow-4.20.0:0/6::gentoo [4.19.3:0/5::gentoo] USE="acl nls pam (split-usr) -audit (-selinux) -skey -su (-systemd) -test -verify-sig (-xattr%*)" 2237 KiB

Total: 1 package (1 upgrade), Size of downloads: 2237 KiB