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

Calculating dependencies ...

!!! Problem resolving dependencies for =media-libs/libmediaart-1.9.7
 done!
Dependency resolution took 0.82 s (backtrack: 0/20).


!!! The ebuild selected to satisfy "=media-libs/libmediaart-1.9.7" has unmet requirements.
- media-libs/libmediaart-1.9.7::gentoo USE="-gtk -gtk-doc -introspection -qt6 -test -vala"

  The following REQUIRED_USE flag constraints are unsatisfied:
    exactly-one-of ( gtk qt6 )

  The above constraints are a subset of the following complete expression:
    exactly-one-of ( gtk qt6 ) vala? ( introspection )