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

Calculating dependencies ... done!
Dependency resolution took 0.91 s (backtrack: 0/20).


!!! The ebuild selected to satisfy "x11-misc/sddm" has unmet requirements.
- x11-misc/sddm-0.21.0_p20260819-r1::gentoo USE="-elogind (-systemd) -test"

  The following REQUIRED_USE flag constraints are unsatisfied:
    exactly-one-of ( elogind systemd )

(dependency required by "kde-plasma/sddm-kcm-6.6.6-r1::gentoo" [ebuild])
(dependency required by "=kde-plasma/sddm-kcm-6.6.6-r1" [argument])