glib2 got updated to 2.81.0, with it it contains gobject-introspection 1.81.2 (the gi commands and python module are now included in the glib-gir-tools package).
Took about a month to get together all the bits, kudos to @madmax and @BiPolar !
Thanks also to @korli for fixing the issue for glib2 in Haiku !
ECM (extra-cmake-modules) has been updated to 6.19.0, with it it fixes the need to declare: ECM_DIR, QTPLUGINDIR, QMLDIR and QCHDIR on Haiku.