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

Calculating dependencies ... done!
Dependency resolution took 1.03 s (backtrack: 0/20).

[ebuild  N     ] sys-fs/lvm2-2.03.39::gentoo  USE="readline udev -lvm -nvme -sanlock (-selinux) -static -static-libs (-systemd) -test -thin -valgrind -vdo -xfs" 2811 KiB
[ebuild  N     ] sys-block/vdo-8.3.2.1::gentoo  238 KiB

Total: 2 packages (2 new), Size of downloads: 3048 KiB