Hmm ... It's impossible ;-) This RPM doesn't exist on any FTP server

Provides :
gimp3-devel
gimp3-devel(x86-32)
pkgconfig(gimp-3.0)
pkgconfig(gimpthumb-3.0)
pkgconfig(gimpui-3.0)
rpm_macro(_gimp3_datadir)
rpm_macro(_gimp3_libdir)
rpm_macro(_gimp3_localedir)
rpm_macro(_gimp3_plugindir)
rpm_macro(_gimp3_scriptdir)
rpm_macro(_gimp3_sysconfdir)

Requires :

/usr/bin/pkg-config
gimp3-devel-tools = 3.0.0~RC1-2.fc39
gimp3-libs(x86-32) = 3.0.0~RC1-2.fc39
libgimp-3.0.so.0
libgimp-scriptfu-3.0.so.0
libgimpbase-3.0.so.0
libgimpcolor-3.0.so.0
libgimpconfig-3.0.so.0
libgimpmath-3.0.so.0
libgimpmodule-3.0.so.0
libgimpthumb-3.0.so.0
libgimpui-3.0.so.0
libgimpwidgets-3.0.so.0
pkgconfig(cairo) >= 1.14.0
pkgconfig(gdk-pixbuf-2.0) >= 2.30.8
pkgconfig(gegl-0.4) >= 0.4.50
pkgconfig(gexiv2) >= 0.14.0
pkgconfig(gimp-3.0)
pkgconfig(gio-2.0)
pkgconfig(gio-unix-2.0)
pkgconfig(glib-2.0) >= 2.70.0
pkgconfig(gmodule-no-export-2.0)
pkgconfig(gobject-2.0) >= 2.70.0
pkgconfig(gtk+-3.0) >= 3.24.0
pkgconfig(lcms2) >= 2.8
pkgconfig(pango) >= 1.50.0
pkgconfig(pangoft2) >= 1.50.0
rpmlib(CompressedFileNames) <= 3.0.4-1
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
rpmlib(PayloadIsZstd) <= 5.4.18-1
rpmlib(TildeInVersions) <= 4.10.0-1

Content of RPM :
/usr/include/gimp-3.0
/usr/include/gimp-3.0/libgimp
/usr/include/gimp-3.0/libgimp/gimp.h
/usr/include/gimp-3.0/libgimp/gimp_pdb.h
/usr/include/gimp-3.0/libgimp/gimp_pdb_headers.h
/usr/include/gimp-3.0/libgimp/gimpaspectpreview.h
/usr/include/gimp-3.0/libgimp/gimpbatchprocedure.h
/usr/include/gimp-3.0/libgimp/gimpbrush.h
/usr/include/gimp-3.0/libgimp/gimpbrush_pdb.h
/usr/include/gimp-3.0/libgimp/gimpbrushchooser.h
/usr/include/gimp-3.0/libgimp/gimpbrushes_pdb.h
/usr/include/gimp-3.0/libgimp/gimpbrushselect_pdb.h
/usr/include/gimp-3.0/libgimp/gimpbuffer_pdb.h
/usr/include/gimp-3.0/libgimp/gimpchannel.h
/usr/include/gimp-3.0/libgimp/gimpchannel_pdb.h
/usr/include/gimp-3.0/libgimp/gimpcontext_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdebug_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdisplay.h
/usr/include/gimp-3.0/libgimp/gimpdisplay_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdrawable.h
/usr/include/gimp-3.0/libgimp/gimpdrawable_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdrawablechooser.h
/usr/include/gimp-3.0/libgimp/gimpdrawablecolor_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdrawableedit_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdrawablepreview.h
/usr/include/gimp-3.0/libgimp/gimpdrawableselect_pdb.h
/usr/include/gimp-3.0/libgimp/gimpdynamics_pdb.h
/usr/include/gimp-3.0/libgimp/gimpedit_pdb.h
/usr/include/gimp-3.0/libgimp/gimpenums.h
/usr/include/gimp-3.0/libgimp/gimpexportoptions.h
There is 3303 files more in these RPM.