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

Calculating dependencies ... done!
Dependency resolution took 0.89 s (backtrack: 0/20).


The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by gnome-extra/gnome-calculator-49.2-r1::gentoo
# required by =gnome-extra/gnome-calculator-49.2-r1 (argument)
>=net-libs/libsoup-3.6.6 vala

!!! The ebuild selected to satisfy "net-libs/libsoup:3.0[vala]" has unmet requirements.
- net-libs/libsoup-3.6.6::gentoo USE="brotli ssl -gssapi -gtk-doc -introspection -samba -sysprof -test -vala"

  The following REQUIRED_USE flag constraints are unsatisfied:
    vala? ( introspection )

  The above constraints are a subset of the following complete expression:
    gtk-doc? ( introspection ) vala? ( introspection )

(dependency required by "gnome-extra/gnome-calculator-49.2-r1::gentoo" [ebuild])
(dependency required by "=gnome-extra/gnome-calculator-49.2-r1" [argument])