It appeared:
Completely unexpected bug in Win Gimp-3.0.0 - no Python plug-ins work.
The unofficially released version of the installer for Windows - GIMP 3.0.0 (version 1) (I think it solves this problem partially) is available at Python Plugins crashes and don't show up (due to lack of libgirepository-2.0-0.dll) (#13170) · Issues · GNOME / GIMP · GitLab
I installed GIMP 3.0.0 v1, correctly run installed plug-ins such as. “Resynthesizer,” “RemoveBG,” “Pandora combine,” “Arrow Designer,” “Flower of Life,” “Yin-Yang.” But G`MiC and e.g. Beautify," no longer.