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

Calculating dependencies ... done!
Dependency resolution took 0.99 s (backtrack: 0/20).

[ebuild  N     ] dev-lang/yasm-1.3.0-r2::gentoo  USE="nls" 1458 KiB
[ebuild  N     ] media-libs/svt-av1-4.1.0:0/4::gentoo  USE="pgo -test -tools" CPU_FLAGS_X86="avx512vl" 47086 KiB

Total: 2 packages (2 new), Size of downloads: 48543 KiB