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

Calculating dependencies ... done!
Dependency resolution took 1.01 s (backtrack: 0/20).

[ebuild  N     ] net-libs/mbedtls-3.6.5:3/16.21.7::gentoo  USE="threads -doc -programs -static-libs -test" CPU_FLAGS_X86="sse2" 5242 KiB
[ebuild  N     ] dev-libs/nng-1.10.1::gentoo  USE="compat deprecated ssl -doc -test -tools" 752 KiB

Total: 2 packages (2 new), Size of downloads: 5993 KiB