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

Calculating dependencies ... done!
Dependency resolution took 1.51 s (backtrack: 0/20).

[ebuild     UD ] dev-perl/XS-Parse-Keyword-0.480.0::gentoo [0.490.0-r1::gentoo] USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 93 KiB

Total: 1 package (1 downgrade), Size of downloads: 93 KiB