To be precise, "app-leechcraft/lc-azoth" depends on ">=net-libs/qxmpp-0.9.3[qt5]". There's only net-libs/qxmpp-0.9.3-r1 in tree (except 0.8, which is too old), and it has no IUSE="qt5" any more. `[qt5]` requirement should be dropped from DEPEND.
Thanks for reporting, fixed in git commit a6e674f49c7f6f7c5c6f22f8b1dbc78df7800405.