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

Calculating dependencies ... done!
Dependency resolution took 1.00 s (backtrack: 0/20).

[ebuild  N     ] x11-libs/libXinerama-1.1.6::gentoo  USE="-doc" 263 KiB
[ebuild  N     ] x11-libs/libXres-1.2.3::gentoo  USE="-doc" 263 KiB
[ebuild  N     ] x11-misc/simpleswitcher-20191008::gentoo  17 KiB

Total: 3 packages (3 new), Size of downloads: 541 KiB